CA1200547A - Antagonists of the antidiuretic action of arginine vasopressin - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE

Compounds are disclosed which act as antagonists of the antidiuretic activity of arginine vasopressin, which compounds are of the formula:

Description

This is a division of application Serial No.
397,464 filed March 3, 19~2.
This invention relates to novel peptides which antagonize the antidiuretic action of arginlne vasopressin in vivo.

~ ttempts to develop clinically useful synthetic antagonists o~ in vivo an~idiuretic and/or vasopressor responses to arginine vasopressln, the antidiuretic hormone ~ADH3, have led to the synthe~l~ and pharmacological evaluation of hundred~ of analogs of the neurohypophysial peptide~, oxytocin and vasopressin.
~ nalogs which can effectively antagonize in vivo vasopressor responses to ADM have been reported by Dyckes et al., J. Med. Chem., vol. 17 (1974) at __ 250 Manning et al., J Med. _hem., vol.20 (1977) at 1228: Bankowski et al., J. Med. _hem., vol. 21 (1978) at 850 Kruszynski et al., J. Med. Chem., vol. 23 (1980) at 364 and Lowbridge et al., J. Med. Chem., vol. 21 (1978) at 313.

Krus~ynski et al. reported that [l-(~-mercapto-~, ~-cyclopentamethylenepropionic acid), 2-(O-methyl)-tyroslne]arginine vasopressin and (l-~-mercapto-~, ~-cyclopentamethylenepropionic acidl-arginine vasopressin are potent vasopressor antagonists, which also have very low antidluretic potency.
Manning et al. (1977) described the synthesis of [l-dea~inopeniciilamine, 4-valine, 8-D-arginine3 va~opressin and Lowbridge et al. the ~ynthesis o [l-(~-mercapto-~ cyclopentamethylenepropionic acid), 4-valine, 8-D-arginine~ vasopressin. sOth of these compounds have weak antidiuretic activity and are potent antagonists of the vasopressor response t~ ~VP.

i~

-~Z(~3()~7 Analogs of vasopressin or oxytocin which antagoni~e antidiuretic responses to ~D~I have been reported by Chan et al., Science, vol. 161 (196~) at 2~0 and J. _ha macol.
~. Ther., vol. 174 (1970) at 541 and vol. 196 (1976) at 746; Nestor et al., J. Med. Chem., vol. l~ 75) at 1022 and Larsson et al., J. Med. Chem., vol. 21 (197R) at 7~6.
None of the compounds reported has been pharmacologically or clinically useFul as an antidiuretic antagonist.
The synthe~is and evaluation of vasopressin analogs, incorporating etherified tyrosine at the 2-position, valine at the 4-position and D- or L-~rg at the 8-position, which antagonize the anti-diuretic act;.on ~H in _~vo have been reported by Sawyer et al., Science, vol. ~12 (1981) at 49 and by Manning et al., J. Med. _hem., vol. 2~ (19Rl) at 701.
Synthetic vasopressins have been disclosed in the follow.ing U~S. Patents:
3,371,080 Boissonnas et al.
3,415,805 Siedel et al.
3,418,3U7 sOissonnas et al.
3~454,549 Boissonnas et al.
3,497,491 Zaoral 4,148,787 Mulder et al.
25 Of these references, Bolssonnas et al., '080 discloses that

2-phenylalanine-R-ornithine vasopressin has a vasoconstric-tive action equal to that of natural vasopressins but low antidiu~etic activity. The remaining re~erences disclose synthetic vasopressins having high or relatively specific

3~ antidiuretic activity.
Synthetic modification~ of oxytocin are disclosed by Mannlng in U.S. Patent~ 3,691,147 and 3,700,652.
.

' i ~LZ()~5g~7 It is therefore apparent that there is a con-tinuing need for the development of pharmacologically and clinically effective antagonists of the anti-diuretic action of arginine vasopressin.
It is an object of the invention to provide 1~ antagoni~ts to the antidiuretic action of ADH, which are effective in vivo.
The parent apPlication relates t~ n,o~?el an-tagonists of the antidiure,tic action of ADII, which are compounds of the formula C112-CO-Tyr(X~Phe-Val-~sn-Cy-W-Z-Gly-N~12 /CH2-C~I
CH C
~ ~I
CH -Cl S S
wherein X'is methyl, ethyl, n-propyl, isopropyl or 2~ butyl, Tyr is D- or L-; W i9 Pro or ~3-Pro and Z is L-or D- Arg.
The parent application further relates to antagonis-ts o~ the ADH activity of arginine vasopressin, of the formula 1 2 3 4 5 6 7 ~ 9 ' CH2-CO-X-Phe-Val-~sn-Cy-Pro-%-Gly-NHz CH -C~
CH C
~CH2-C~I '1 s wherein X is D-Phe, D-Val, D-Leu, D-Ile, D-~rg, D-norvaline, 3~ D-norleucine, D-cyclohexylalanine, D-~-aminobutyric acid, D-threonine or D-methionine and 7, is D- or L~rg.

:~ ~t~ S~'7 3a The parent aPPlication also provides a Process for the production of a compound of the formula ~ ~ Ct~2-CO-X-Phs-~tal~ n~-Cy-W-Z-Gly-N112 (CT~2 ) C . .'.

~ S ' S
whereln X is Tyr-X', D-Phe, D-Val, D-Lou, D-Il~ Arg, -norval~ne, ~-norlauc~n~, D-cvcloh~xylalan~ne, D-~'-amlno-butyric acid, D-threonine or D-methionine; X' is methyl, ethyl, n-propyl, isopropyl or butyl, Tyr is D- or L-;
butyrlc ac~d, D-threon~n~ or D-~ethlorl~n~; Tyr ~ ~- or L-S
Pro or ~ -Pros Z ~ D- or L-~rg and, when X is Tyr-~', W 1~ ~-Pro1 whlch comprl~ the st~ of:
(a3 trea~ing ~oG-~ly-reqin by ~olld phas~ ~ynthesl~
by qlx cyclo~ of deprotectlon, n~utrallzatlon and coupllng wlth a ~lected amlno acld to pxoduce a corr~.qpond~ng pro-t.ect~a h~ptapeptldyl re~ln of the formula Boc-Phe-Val-~qn-Cy(~zl)-~ or ~ r~(Tos)-51Y-reslh wl~er~in W 19 as above;
(b) tr~atlng the corr~s~ona~n~ p~ot~ct~d heptapeptldyl resln producea in step ~a) by ~olid pha~e pe~tld~ .qynth39l~
.~n a cycle of ae~rotectlon, neutral~z~tlon and coupllng wlth Boc-X to proauc~ a corresponalng ter~-b~toxycarbonyl-octapeptlayl re~ln of t~ ~ormula E~oc-X-Phe-Val-A~n-Cv tBZl) -~- (D- or L-)~rq (To~ -rQsln (c) ammonoly21ng the corresnondln~ prot~c~e~t octapeptldyl r~sln producea ln ~t~p (b) to a corre~pondlng Boc octap~ptide amlde of thQ ~ormula Boc-X-Ph~Val-A~n-Cy (B~l) -W- (D- or L-~ rg (To~ 31y-NH2 ~ .
whereln X ~g a~ above S
~ a) converltlng ~he correspona~ng!~oa-octapept:Lae amlde produc~d ln ~tep tc) to a corresponalng ~-(S~benzyl-marcapto)~ -cyclopentamethyleneproplonyl-o~tape~t~ a~
am~d~ of the formula 5~L~7 3b C~2CO-X-Ph~--~al-Cy(~3zl)-W-~D- or L-)Arg(Tos)-~ly-~2 (Clt2) 5 ~ _ /S-CH2Ph by coupllng a neu-tralizod, doprote~te~ solutlon of a corre~ponaing t~rt-butoxyc~rbonyl--octapept~de am.~da wlth p-nltrophenyl-~-(5-benzylm~rcapto)-~,~-cyclopen-tamethylene proplonat~, ln the pr~ence o~ ~-hy~roxy-banzotrl~201~ monohydrate ana ~a) r~7duaing a corre~ponding ~(S-benzylmerGapto1-cyclop~ntamethylsn~-l?rop:LonylocltapQ!?tiae am~ae produced ln st~p (d) w~th soal~m in llquld ammonia and oxldatively ayall~ing n r~ultlng dl3ulfhydryl compound wlth pota~ um ~rrlcyani~e, .

)5~7 This inven-tion further relates to a method for antagon-izing the in vivo response to ADH, comprising administering to an animal being reated an amount of one of -the foregoing compounds, in admixture with a physiologically and pharma-ceutically accep-table carrier, effective to antagonize the antidiuretic response to ADH.
The present invention rela-tes to an-tagonists of -the antidiuretic action of ADH, the compounds being of the for-mula ~ CIH2-CO-Tyr(h)-Phe-Val-Asn-Cy-Pro-Z-Gly-NH2 ( 2)5 Cl \ S ''' wherein Tyr- is D-Tyr and Z is L- or D- Arg. These compounds can be used in vivo for antagonizing the an-tidiuretic res-ponse to a vasopressor hormone in an animal being treated.
Aecordingly, the invention provides a process for the production of a compound of the formula ~ ICH2-CO-Tyr(h)-Phe-Val-Asn-Cy-Pro-Z-Gly-NH2 ( 2)5 C
~ S S

wherein Tyr is D-Tyr and Z is D- or L-Arg, which comprises the steps of, (a) treating Boc-Gly-resin by solid phase synthe-sis by six eyeles of deproteetion, neutralization and coupling with a selected amino acid to produce a corresponding pro-teeted heptapeptidyl resin of the formula Boc-Phe-Val-Asn-Cy(Bzl)-Pro-Z(Tos)-Gly-resin, wherein Z is as above, ~b) treating the corresponding protected heptapeptidyl resin produeed in step (a) by solid phase peptide synthesis in a cycle of deprotection, neutralization and coupling with Boc-D-Tyr(H~ to produce a corresponding tert-butoxy-carbonyloctapeptidyl resin of -the formula Boc-D-Tyr(H)-Phe-Val-Asn-Cy(Bzl)-Pro-Z~Tos)-Gly-resin, wherein Z is as above, (c) ammonolyzing the corresponding -~2~ 7 4a protected octapeptidyl resin produced in s-tep (c) to a corres-ponding Boc-octapeptidyl amide oE the formula soc-D-Tyr(H)-Phe-Val-Asn-Cy~szl)-Pro-Z(Tos)Gly-NH2, (d~ converting the corresponding Boc-octapeptide amide produced in step (c) to a corresponding ~-(S-benzylmercapto)~,~-cyclo-pentamethylenepropionyl-octapeptide amide of the formula f~ CH2-CO-D-Tyr(H)-Phe-Val-Asn-Cy(Bzl)-Pro-Z(Tos)-Gly-NH2 (CH2)5 IC
~-- S -CH2Ph by coupling a neutralized, deprotected solution of a corres-ponding tert-butoxycarbonyl-octapeptide amide with p-nitrophenyl-~-(S-benzylmercapto)-~,~-cyclopentamethylene pro-pionate, in the presence o N-hydroxybenzotrizaole monohydrate and (e) reducing a corresponding ~-(S-benzylmercapto)-/~
cyclopentamethylenepropionyloctapeptide amide produced in step (d) with sodium in liquid ammonia and oxidatively cyclizing a resulting disulfhydryl compound with potassium ferricyanide.
In the accompanying drawings:
Fig. 1 shows urine osmolalities, as a function of time, of rats treated intraperitoneally with an active compound;
and Fig. 2 shows urine output, as a function of time, of rats treated with an active compound.
Compounds provided in accordance with the invention or that of the parent application are derivatives oE arginine vasopressin (AVP). Amino acids are in the L- form unless otherwise indicated. The correlation between full names and abbreviations is:
dAVP, l~deamino-arginine vasopressin; dPAVP, [l-deamino-penicillamine] arginine vasopressin; d(CH2)5AVP, [1-(~-mercapto-~,~-cyclopentamethylenepropionic 5~'~

acld)~-arginine vasopressin: dvD~vP, l-deamino[~-valine, 8-D-arginine] vasopres~in; dPVD~VP, ll-deamino--penicillamine, 4-valine, 8-D-arginine] vasopres.sin;
d(CH2~5VDAVP, [l-(~-me.rcapto-~,~-cyclopenta-methylenepropionic acid), 4-valine, 8-D-a.rginine]
vasopressin; dTyr(Me~VP, l-deamino[2-(0-methyl)-tyrosine] arginine vasopressin; dPTyr(Me)AVP [l-deaminopenicillamine, 2-(0-methyl)tyro~ine] arginine vasopressin; d(CH2)5Tyr(Me)VDAVP, [l-(~-mercapto-~, l~ ~-cyclopentamethylenepropionlc acid), 2-0-methyltyrosine,

4-valine, 8-D-ar~inine] vasopressin; d(CH~)5Tyr(Et)VD~VP, [l~(~-mercapto-~,~-cyclopentameth~lenepropionic acid), 2-0-ethyltyrosine, 4-valine, 8-D-arginine] vasopre~sin, d(CH2)5Tyr(Me)VAVP, ll-(~-mercapto-~,~-cyclopenta-methylenepropionic acid), 2-to-methyl)tyrosine~ 4-valine]
arglnine vasopress.in; d~C~I2)5Tyr(Et)V~VP, [l-(~-mercapto-~,B-cyclopentamethylenepropionic acid), 2-0-ethyltyrosine, ~-valine] arginine va~opressin;
d~CH2)5Tyr(i-Pr)VD~VP, [l-(~-mercapto-~,~-cyclopenta-methylenepropionic acid), 2-(0-i~opropyl)tyrosine, 4-valine, 8-D-arginine] vasopressin; d(C~I2)51yr~n-Pr~-VD~VP, [l-(~-mercapto-~,~-cyclopentamethylenepropionic acid), 2-(0-n-propyl)tyrosine, 4-valine, 8-~-argininel vasopressin; d(Cli2)$Tyr(i-Pr)VAVP~ -me,rcapto-~
~-cyclopentamethylenepropionic acid), 2-(0-isopropyl) tyro~ine, 4-valine] arginine vasopressin;
d(CH2)~Tyr(n-Pr)V~VP, [l~ mercapto-~,~ -cyclopenta-methylenepropionic acid), 2-(0-n-propyl)tyrosine, 4-valinel arginine vasopressin; and d(CH2)5Tyr(Et)V a -Pro AVP, ~ -mercapto-~,~ -cyclopentamethylenepropionic acid), 2-(0-e-thyl)tyrosine, 4-valine, 7-~3,4-dehvdropro-line)~ arginine vaso~ressin; d(C~I2)5- D-Tyr VDAVP, -mercapto-~,~-cyclopentamethvlene- propionic acid), 2-D-tyrosine, 4-valine, 8-D-arginine vasopressin, d(CH2)5 D-Tyr V~VP, ~ -mercapto-~,~-cvclopenta-methylenepropionic acid), 2- n-tyrOsine, 4-valin~ -arginine vasopressin; d(CTI2)5-D-~he vn~vP/

~f~ 7 C~ merc~to-~,~-cvclopentamethy:l~n~propionic acid), 2-D-phenyli~ nine, 4-vi~lin~, 8-D-ar~inin~
vasopressin; d(Cll2)5 D-Phe V~VP, [l~-mercilpto-~ cyclopentamethyleneproplonic acid), 2-D-phenylalanin~, S 4-valine]-ar~inine v.~sopressin; d(Cll2)5 lGly21 V~VP, [l-(~-mercapto-~,~-cyclopentamethylerlepropionic ~cid), 2-glycine, 4-vallne~-arginlne vasopre~sin ~(C1l2)5-lD-Ala ~ V~VP, [1-(~-merCilpto-~ -cyclop~ntamethylenepro-pionic acid), 2-D-alanLne~ ~-valine~ rginine vasopressin:
r) d (C112) 5 ~{) Val21 V.l\VP ~ -merc~pto-p ~ -cyclop~ntamc!th lenepropionic acid), 2-D-valine, ~-v~line]-ilrclinine vasopressin, cl(Cll2)5 [D-Leu ] V~Vl?, Il-(~-mercapto-~
cyclopentamethylenepropiot-ic acicl), 2-D-Le~lc:ine, ~-valine~-ar~inine va~sopressin; d(CI-I~)r [~-Ile2] V~VP, 1~ [l-(~-mercapto-~,~-cyclopentamethylenepropiollic acid), 2-D-isoleucine, 4-valine]-ar~]inine vasopressill; and d(C~l2)5 [D-Arg2] VAVP, [l-(~-mercapto-~,~cyclopentamethy-lenepropionic acid)~ 2-D-ar~inine, ~-valine]-arginine vasopressin.
The active peptides were synthesized by solid phase synthesis as described b~ Bankowski et al. (1978), su~ra;
Merrifield, J. ~tm Chem. Soc., vol. 85 (1963) at 21~9 and Biochemistry, vol. 3 (1964) at 13n5; Mannin~, J. ~m. Chern.
Soc., vol. 90 (1968) at 1348; Manning et al., J. Med. Chern., vol. 19 (1976) at 376; ~owbriclge et ~1., J. Me~. _hern., vol. 20 (1977) at 1173; Manning et al., J. Me~. _hem., vol. 16 (1973) at 975; Kruszynski et al. (19~0), ciu~)ra:
Sawyer et al., (1981), _u~ra or Mallnin~ et al. (19Bl) supra.
~n Peptides containing ~3-Pro in the 7-position were also prepared in this fashion. Incorporation of ~ 3-Pro into peptides has been described by Felix et al., J. Peptide Protein Re , vol. 1~ (1977) at 299 and nOtos et al., J. Med. Chem., vol. 22 (1979) at 926.
Initlal attempt~ to design an antagonist of the antidiuretic response to arginlne vasopressin (AVP) included synth~sis of [l-deaminopenicillamine, 4-valine, 8-D-arginine] vasopressin (dPVD~VP) by Manning et al. (1977), suJ~ra, ancl of [l-(~-mercapto-~, ~-cyclopentamethylenepropionic acid), ~-valine, 8-D-arginine] vasopressin (d(CH2)5VD~VP), Lowbridge (1978), ~ a. The~se analog~ were designed by replacing the two hydrogens on the ~-carbon at the 1~ position of the highly active and selective antidiuretic peptide l-deamino~4-valine, 8-D-arginine] va~opressin (dVDAVP), Manning et al., J. Med. Chem., vol. 16 (1973) at 975, by two methyl groups and a cyclopentamethylene group, respectlvely.
These substituents had previously been shown to convert the highly potent oxytocic agonist l-deamino-oxytocin (dOT) into potent ~ntagoni~ts of the oxytocic response to oxytocin, specifically, [l-deaminopenicillamine~ oxytocin (dPOT) and ll-(p-mercapto~ cyclopentamethylenepropionic acid)~ oxytocin (d(CH2~50T). See, ilope et al., ~n J. siol. _hem., vol. 237 ~1962) at 1563, Schulz et al., J. Med. Chem., vol. 9 (1966) at 647 and __ Nestor et al., J. Med. _hem., vol. 18 (1975) at 284.
Surprisingly, neither dPVD~VP nor d(CH2)5VD~VP
was an antagonist of the antidiuretic response to ~VP although possessing 0.1 and only 0.0001 the antidiuretic activity of dVDAVP, respectively.
Each, however, was a potent antagonist o the vasopressor response to AVP, expressed as P~2.
3~ P~2 represents the negative logarithm to the base 10 of the average molar concentrations of ~ntagonist which will reduce the specific biological response to 2x units of an agonist to the level o response to x units of the agonist. dPVDAVP and d(CH2)5VDAVP
3S had antivasopressor PA2 values of 7.82 and 7.68, respectively.

~2~.~(.)5~7 The discovery of these two vasopressor antagonists dPVDAVP and d(CH2)5VD~VP led to exploration of the ef~ects of ~ dimethyl and ~ cyclopentamethylene s~lhstitutions at the 1-position in other analocJs of AVP, partic~llarly incombination with t)-e substit-utioll of O-methyltyrosine at the 2-position of the highly active antidiuretic and vasopressor ag~nist l-deamino-ar~1:inine vasopressin (dAVP) in hopes of obtaLning an antivasoE)reC;~or 1~ peptide even more potent and selective than dPVD~VP
or d(CH2)5VDAvP. See, Huguenin et al., ~lelv. Chem.
Acta., vol. 49 (1966~ at 695; Manning et al., J. Med.
Chem., vol. 19 (1976) at 842 and Law et al., J. ~m.
Chem. Soc., vol. 82 (1960) at 4579.
__ __ The discovery of the antidiuretic anta~onists d(CH2)5Tyr(alk)VAVP, Sawyer et al., (19nl), ~su~ra, Manning et al., (1981) ~ra, led to the synthesis of Otller pOSitiOII two substituted analogs. ~nhanced antl-antidiuretic poten~ies were ex}libited by the various 2~ O-alkyl D-tyrosine analogs, Mannin~ et al., in Peptides, Struture, Function, Dan ll. ~ich and E. Gross, eds., Pierce Chemical Co (in press) and J. Mecl. Chem. (submitted).
The unalkylated D-tyrosine isomers of d(C~12)5VD~VP and d(CH2)5VAVP, i.e., d(C~12)5D-Tyr-VDAVP and d(Cll2)5D-Tyr-V~VP
were also shown to be arlti-antidiuretics. ~ttempts to further enhance anti-antidiuretic potency and selectivity have led to the synthesis of analogs of d(C~l2)5D-Tyr2VAVP
and d(Cll2)5D-Tyr VDAVP containing other D-amino acids in place of D-tyrosine at position two, in accordance with 3~ the present invention.
It was surprisingly founa by Bankowski et al.
(1978), supra, that of ~l-deaminopenicillamine~-arginine vasopressin (dPAVP) an~ [l-deaminopenicillamine, 2-(O-methyl)tyrosine] arginine vasopre~sin (dPTyr(Me)-~VP), dPAVP was less potent than~either dPVDAVP or

5~7 d(CH2)5VD~VP but dPTyr(Me)~VP had an antiva~opre~sor P~2 of 7.96 and was the most potent antiv~sopressor peptide then known.
The effect, on antiva~opressor potency of combining the ~ cyclopentamethylene and 0-methyltyrosine substitutions in d~VP was developed [l-(~-mercapto-~cyclopentamethylenepropionic ~cid), 2-(0-methyl)-tyrosine]-argini~e vasopressin (d(C112)5Tyr(Me)~VP) of the structure 1~ 1 2 3 ~t 5 fi 7 8 9 CH2-CO-Tyr(Me)-Phe-Gln-Asn-Cy-Pro-l~rg-Gly-N~12 /C112-C~ I
C~ ~ 1 C~l -Cl S

~5 ~This compouncl had ver~ hi~h antivasopresso~ potency and very weak antidiuretic activity, as did the unmethylated 2-tyrosine derivative, d(C~12)5~VP and these compounds form Part o~ the subiect matter of -the copending divisional application filed of even date herewith.
The compounds of the invention of the parent applica-tion Serial No. 397, 464 which have activity as antagonists of the antidiuretic activity of arginine vasopressin belong to the 4-valine-8-arginine vasopressin series and are of Formula I

CH2-CO-Tyr(X)-Phe-Val-Asn-Cy-Pro-Z-Gly-NH2 / 2 C ~ l C ~ / IC

wherein Tyr is D- or L- and X' and Z are:

-~L2(~5~

l!) X' %
Me D-~rg Et D-Arg Me ~-~r~
Et L-~rg i-Pr D-Ar~
n-Pr D-~r~
1-Pr L-~rg n-Pr L-~rg ~u L- or D- Arg Compounds of Formula II are as above, wherein Pro at the 7-position is replaced by ~3~Pro.
The compounds of Formula I are related to a previously-reported antagonist of vasopressor responses to ADII, Il-(~-mercapto-~,~-cyclopentamethyl-enepropionic acid), 4-valine, 8-D-arginine] vasopressin d(CH2)5VDAVP, Lowbridge et al. tl978). Althoug not an antagonist of antidiuretic response~ to ~DH in _ lVO, this analog was a competitive antagonist of the activat~on of renal medullary adenylate cyclase by ~DH
in v tro, Butlen et al., Mol. Pharmacol., vol. 14 (1978) at 1006. The work of Larsson et al. (1978), s~ra, also indicated the feasibility of making O-alkyl-tyrosine substitutions to convert thi~s type of peptide into an 2S antagonist of the antidiuretic response in _ivo.
Compounds of Formula II contain a ~ -Pro unit thought by ~otos et al., supra, to contribute to hi~h antidiuretic activity of certain AVP analogues.
As shown by intraperitoneal administration of these compounds to normally-hydrated conscious rats, (O-ethyl)-tyxosine substitution at the 2-position in compounds of Formula I is more effective than (O-methyl)tyrosine substitution. The tO-proPyl)-tyrosine compounds of Formula I also have impr~ssive anti-~DH activity. Ilowever a 2-(O-Et)-tyrosine (.}5~

compound of Formula II is the most effective anti-~D~I
compound evaluated to present. The 8-L-arginine analogs are more potent than the correspondi~g 8-D-arginine analogs.
It appears that higher doses of d(Cll2)5Tyr(Et)V~VP
almost completel~ block the antidiuretic action of endogenous ~DII. For example, the 30 pg/kg dose of d(CH2)5Tyr(Et)VAVP raised urine flow to a mean o 27 ml/kg per hr during the second hour after injection.
Spontaneous urine flow in female rats homozygous for the Brattleboro strain that secrete no ~D~I at all averages 32 ml/kg per hr, Sawyer, et al., Endocrinology, vol.
95 (197~) at l~0.
The importance of minor structural modificatlons is indicated by findlngs that corresponding ~ diethyl and~ dimethyl an~logs of d(CH~)5Tyr(Et)V~VP do not exert detecta~le antagonistic act~vity in the intravenous rat antidiuretic assay. The prese,nce of the 4-valine also contributes to antagonistic activity; Substitut~on of a 4-glutamille unit in d(CH2)5Tyx(Et)V~VP results ~n loss of antagollistic activity.
Compounds of the invention of the copending divisional application having Gln in the 4-position, which antagonize the vasopressor response to AVP, are useful in pharmacological studies on the role of AVP in regulating blood pressure under normal and pathophysiological conditions. Clinical applica-tions include use as diagnostic and therapeutic antihyperten-sive agents. For therapeutic purposes, these compounds willbe used in the same fashion as the known antihypertensive drug Captopril, D.B. Case et al.~ "Progress in Cardiovascular Diseases," vol. 21 ~1978) at 195.
The compounds of Formulas I and II are very effective antagonists of the antidiuretic response to ADH.
They can therefore be used in pharmacological '7 studies on the con-tribution of ADH to a variety of pathological states involving water retention. I-t is further contemplated that they could be effec-tive and specific agents for treating the syndrome of inappropriate secretion of ADH, that is, the Schwartz-Bartter Syndrome or SIADH. This syndrome can complicate a number of disorders, including carcinomas, pulmonary diseases, intracranial diseases and head injuries, Bartter et al., 10 Am. J. Med., vol. 42 (1967) at 790.
It was found that some d(CH2)5VAVP derivatives having a D-amino acid other than tyrosine and larger than alanine in the 2-position are more potent antagonists of the anti-diuretic action of AVP than compounds having D- or L-tyrosine ether units or a D-tyrosine unit at the 2- position of d(CH2)5VAVP or d(CH2~5VDAVP.
As shown by intravenous administration of the compounds of the parent invention to normally-hydrated conscious rats and to hydrated rats anesthetized with ethanol, compounds having D-Phe, D-Val, D-Leu or D-Ile substituents a-t the 2-position have high PA2 values and effective doses near or lower than the lowest effective doses known heretofore.
Compounds of the parent invention having D-Phe, D-Val, D-Leu or D-I].e at the 2-position and Arg a-t the 8-positlon are also pure antidiuretic antagonists, i.e., these compounds have no transient antidiuretic agonism. Moreover, these compounds are more selective in their activity, by virtue of high anti-ADH/antivaso-pressor activity ratios, than known compounds.

The compoun~.s of this invention carl be em~loye~l inmixture with conventional excipien~:s, i.e., physioloc3ically and pharmaceutically acceptable organlc or ino~ nic carriers suit~lble for parenteral or ell~er~l ~pp)ic~ntion, which do not interact deleteriously with the ~ctive compounds.
Suitable pharmaceutically acceptable c~rr;ers include, but are not limited tOr water, salt solutions, alcohols, vegetable oils, polyethylene qlycols, gelatine, lactose, amylose, magnesium stearate, talc, silicic acid, 1~ viseous paraffin, perfume oil, fatty acicl monoglycericles and diglycerides, pentaerythritol fatty acid esters, hydroxy-methylcellulose, polyvinyl pyrrolidone, etc.
The Pharmaceutical preparations can be sterili7ed and iE
desired mixed with auxiliary agents, e.g., lubricants, preservatives, stabilizers, wetting agents, emulsiEiers, salts for influencing osmotic pressure, buffers, coloring, flavoring and/or aromatic substances and the like whicl do not deleteriously react with the active eompouncls.
For parenteral ox intranasal application, solutions, 2n preferably aqueous solutions, as well as suspensions, emulsions, or implants, inctuding suppositories, are particularly suitable. ~mpoules are convenient unit dosages.
The compounds of this invention are generally administered to animals, including but not limited to mammals, e.g., livestock, household pets, humans, cattle, cats and dogs. ~ diuretically effective daily dosage oE
the active com~ounds can be administered parenterally in a single dosage or as divided dosages throughout the 3~ day.

Parenteral or intrana~al administration is preferred, the an-ti-antidiuretic com~ounds of thi~s invention being particularly valuable itl the treatment of humans afflicted with water retention oE any etiology.
In this regard, they can ~e administered in substantially the same manner as the known compounds oxytocin and vasopressin, to achieve their physiological effects.
It will be appreciated that the actual preferred n amounts of active compounds used will vary according to the specific compouncl being utilized, the particular compositions formulated, the mode of application, and the particular organism being treated. Optimal application rates under/in a given set of conditions can be ascertained by those skilled in the art of using conventional dosage determination tests in view of the above guidelines.

Preferred antidiuretic antaqonists o~ the parent 2~ i~vention are [l-(~-mercapto~ cyclopentamethylene-propionic acid), 2-(0-ethyl)tyrosine, 4-valine]-arginine vasopressin, most preferably the 8-L-arginine compound. ~lso preferred is a corresponding ~3-Pro7 compound.
~ther preEerrèd compounds are those wherein X
is D-Phe, D-Val, D-Leu or D-Ile and 2 is L-~rg. The D-Ile or D-Phe compound is most preferred.

'5~7 Without further elnboration, it i9 believed that one skilled in the art can, u~ing the preceding description, utili~e the present inventlon to its fullest extent. The following specific embodiments are, therefore, to be construed as merely illustrative and not limitative of the remainder of the disclosure in any way whatsoever. In the following Examples, the temperatures are set forth uncorrected in degrees Celsius. Unless otherwise ln indicated, all parts and percentages are by weight.
Chloromethylated resin (Bio~Rad*~io-13eads SX-l) was esterified by the procedure o Gisin, Helv. _him. ~cta, vol. 56 (1973) at 1~76 with Boc-Gly until O.~7 mmol/g and rvO.h~4 mmol/g were inoorporated. ~mino acid derivatives including Boc-Tyr(Me) (Rf (A) 0.7; Rf (B) 0.8) were supplied by Bachem Inc., or synthesi~ed.
Triethylamine (TE~) and N-methylmorpholine (NMM) were distilled ~rom ninhydrin.
~n ~cetic acid used as the HCl-acetic acid `
cleavage reagent was heated under reflux with boron triacetate and dtstilled from the reagent.
Dimethylformamide (DM~) was distilled under reduced pressure immediately before use. Methanol ~S was dried with magnesium methoxide and distilled.
Other solvents and reagents were o analytical grade.
Thin layer chromatography (TLC) done on silica gel plates (0.25 mm, BrinkmannSilplate) 3n using the ollowing solvent systems: ~. cyclo-hexane-chloroform-acetic acid (2:8:1 v/v);
B. propan-l-ol-ammonia (3~) (2:1 v/v); C. ethanol * Trademarks ()S4L'~

1~

(95~)-ammonia (34%) (3:1 v/v); D. chloroform-methanol (7:3 v~v); E. butan-l-ol-acetic acld-water (4:1:5 v/v, upper phase1; P. butan-l-ol-acetic acid-water-pyridine (15:3:3:10 v/v). The applied loadings were 10-50 p~. The minimum length of the chromatoqrams was 10 cm.
Chloroplatinate reagent and iodine vapor were used for development of the chromatograms.
Amino acid analysis of the peptides was done by the me~lod of Spackman et al., ~nal.
Chem., vol. 30 (195fl) at 1190, in which peptide samples weighing about 0.5 mg were hydrolyzed with constant boiling hydrochloric acld (~00 ~1) in evacuated and sealed ampules for 18 h at 120 C.
The analyses were performed using a Beckman ~utomatic Amino ~cid ~nalyzer, Model 121. Molar ratios were referred to Gly = 1.00. Elemental analyses were performed by Galbraith Laboratories, Inc., Knoxville, Tenn. The analytical results for the elements indlcated by there respective symbols were within ~ 0.4~ of theoretical values.
Optical rotations were measured with a Bellingham Stanley, Ltd., Model A polarimeter, type pl.
EX~MPLE 1 ~ (S-Benzylmercapto)~ -cyclopentamethylene-~ropionyl-Tyr~Me)-Ph~e-Gln-~sn-Cys(~zl)-Pro-~rg (Tos) -~ly-NH2.
(a) Combination of Solld Phase and Solution Methods.
Boc-Tyr(Me)-Phe-Gln-~sn-Cys(Bzl)-Pro-~rg(Tos)-Gly-NH2, prepared by the method of Bankowski e-t al.!
J. Med. Chem., vol. 21 (1976) at 8~2 (319 mg, 0.26 mmol), was dissolved in TEA (6~5 ml) and stirred at room temperature for 40 mins. Cold ether (20 ml) was added to produce a precipitate which was filtered and washed with ether (5 x 10 ml). The product was dried 1~

~(3~7 vacuo over sodium hydroxide pellet~. Thi~ material (318.5 mg) was dissolved in DMF (0.8 ml), to which was added N-methylmorpholine (10 ~1). The resulting solution had ~ pEI of 7-8, me~sured with noifit pl~
paper. ~fter this neutralized solution was stirred at room temperature for 30 min, a solution of p-nitrophenyl ~ (S-benzyl-mercapto)-~,~ -cyclopentamethyl-e~epropionate, Nestor et al., J. Med. Chem. vol. 18 ~1975) at 284, (445 mg, 1.155 mmol in 0.4 ml of DMF) was added. The reaction mixture was stirred at room temperature. ~fter 72 hours' stirring, TLC
analysis u~ing system D showed that the reaction mixture still contained a trace of the free octapeptide amide. N-l~ydroxybenzotriazole monohydrate, Konig et al., C _ . Ber., vol. 103 (1970) at 788, (39.3 mg, 0.26 mmol)_ was added. Coupling was complete within 5 hours.
The precipitate was filtered, washed with cold ethyl acetate (4 x 10 ml) and dried _ vacuo. The crude product (330 mg) was twice reprecipitated from DMF-methanol to give the acylpeptide amide (295.2 mg, 77.3~): mp. 209-211C; [~]D2~ 3.6 (C 0.5, DMF);
Rf(E) 0.45, R~(F) 0.63 ~nal. (C73 H94Ol4S3) C, ~, N.
~mino acid analysis: Tyr, 0.80; Phe, 1.01;
Glu, 1.04; ~sp, 1.02; Cys(Bzl), 0.98; Pro, 1.06;
Arg, 1.01; Gly, 1.00; NH3 2.91.
(b) Total Synthesis on Resin.
Boc-Tyr(Me)-Phe-Gln-~sn-Cys(Bzl~-Pro-Arg(Tos)-Gly-resin (1.11 g, 0.4 mmol prepared from Boc-Gly-resin using solid phase methodology) wa6 converted to the acyloctapeptide resin (1.167 g, weight gain 57 mg, 97.6% of theory) in one cycle of deprotection, neutralization and couplihg with p-nitrophenyl-~S-benzylmercapto)-~,~ -cyclopentamethylenepropionate, see Nestor ~E~a. The resin was ammonolyzed, Manning, J. ~m. Chem. Soc., vol. 90 (1968) at 1348. The product was extracted with dimethyl-formamide (DMF). After the solvent was evaporated in vacuo, the resldue was precipitated by addition of water. The crude product (~10 mg) was twice reprecipitated from DMF-ethanol to give the acyloctapeptide (302 mg, 50.7~ based upon initial glycine content of the xesin); mp. 206-208C
(decomp); Rf (E), 0.45, Rf (F) 0.63; ~]D = -43.1 (C 1, DMF). Anal. (C73H94N14S3) Amino acid analysis: Tyr, 0.79; Phe, 1.01;
Glu, 1.03; Asp, 1.04; Cy~(~zl), 0.97; Pro, 1.03;
Arg, 0.99; Gly 1.00; N~13, 2.g5.

p-(S-Benzylmercapto)-p~ -cyclopentamethylenepropionyl-Tyr(Bzl)-PIle-Gln-~sn-Cys~B~l)-Pro-~rg(Tos)-Gly-NII2.
Boc-Tyr (~7.1) -Phe-Gln-Astl-Cys(Bzl)-Pro-Arg(Tos)Gly-resin (1.~6 g, 0.5 mmol) was converted to the acyloctapeptide resin (1.55 g, weight gain 70 mg, 95.9~ of theory) a~ in Example 1 by one cycle of deprotection, neutralization and coupling with p-nitrophenyl ~-(S-benzylmercapto)~ -cyclopenta-methylenepropionate. The product obtained by ammonolysis of the resin was extracted with DMF.
The solvent was evaporated in vacuo and the residue wa~ precipitated by addition o water.
The crude product (723 mg) was reprecipitated from D~F-ethanol and DMF-2~ aqueous AcOH. (488 mg;
62.4% based on initial Gly content on the resin);
mp. 183-185C; Rf(E) 0.38t Rf(D) 0.41; [~]D = -32~9 (C 1 DMF). ~nal.(C79H98Nl4Ol4 3 Amino acid analysis: Tyr, 0.97; Phe, 1.02;
Glu, 1.05; ~sp, 1.01; Cys(Bzl), 0.98; Pro, 1.04;
Arg, 0.98; Gly, 1.00; NH3.

t~ 5~

EX~MPLE 3 [1-(~ Mercapto-~ cyclopentamethylenepropionic ~cid), 2-(O-methy~)tyro3ille]argilline vasopressin.
(a) From Nonapeptide ~mide ~ solution of the protected nonapeptide amide, prepared as in Example 1, (170 mg, 0.114 mmol) in 400 ml of ammonia (dried over sodium and redistilled) was stirred at the boiling point with sodium from a stick of the metal contained in a ~small bore glass tube unt~l a light blue color persisted in the solution for 30 sec, in accordance with duVigneaud, J. ~m. Chem Soc., vol. 76 (1959) at 3115. Dry glacial acetic acid ~0.4 ml) was added to discharge the color. The solution was evaporated. ~ solution of the residue in aqueou~ acetic acid (0.2R;
800 ml), was treated with 2M ammonium hydroxide solution to give a solution of pH 7.5. To this stirred solution was added gradually an excess of a solution of potassium ferricyanide (O.OlM, 11.4 ml), Hope et al., J. Biol. Chem., vol. 237 (1962) at 1563. The yellow solution wa~ stirred for 90 min more and for 1 h with anion-exchange resin (BioRad ~G-3, Cl form, 10 g damp weight).
The suspension was filtered slowly through a bed of resin (80 g damp weight). The resin bed was washed with 300 ml of aqueous 0.2~ acetic acid and the combined filtrate and washings were lyophylized. The resulting powder (1386 mg) was ` desalted on a Sephadex G-15 column tllO x 2.7 cm) and eluted with aqueou~ acetic acid (50~) at a flow rate 4 ml/h by the technique of Manning et al., J. Chr~matog., vol. 38 (1968) at 396.
The eluate was fractioned and monitored for absorbance of 280 nm. The fractions comprising the major peak were pooled and lyophylizedO The * Trademarks ('5~7 2~

resldue (55.5 mg) was further subjected to gel filtration on a Sephadex G~15 column (100 x 1.5 cm) and eluted with aqueous acetic acid (0.2M) at a flow rate of 2.5 ml/h. The peptide was eluted in a single peak (~bsorbance 280 nm). Lyophilization of the pertinent fractions yielded the vasopressin analoq (49 mg, 37.3~) Rf(E) 0.19; ~f(F) 0.30;
~]D22_59.6 (cO.l9, lM AcOH).
~mino acid analysis: Tyr, 0.81: Phe 1.01;
Glu, 1.04; Asp, 0.9M; Pro, 1.04; ~rg, 0.95; Gly, 1.00;
NH3, 3.10. Analysis f~llowing perfo.rmic acid oxidation p.ri.or to hydrolysis according to Moore, J. Biol. Chem., vol. 238 (1963) at 235, qave a .
Cys(0311)-Gly ratio of 1.03:1.00.
(b) ~rom Acyloctapeptide.
Treatment of the acyloctapeptide (160 mg, 0.107 mmol~ as described in Example 3 (a) yielded the analog t64 mg, 51.7~), which was indistinguishable from the foregoing preparation by TLC: 1~123D -59.1 (C 0.5, lM ~cOH).
~mino acid analysis: Tyr, 0.80; Phe, 1.02 Glu, 1.02; ~sp, 0.98; Pro, 1.03; ~rg, 0.96;
Gly, 1.00; Nl13, 3.05. ~nalysis following perormic acid oxidat.ion prior to hydrolysis gave a Cys-(03H1-Gly ratio of 1.02:1.00.

[l-(~-Mercapto-~r ~-cyclopentamethylenepropionic acid'))arginine ~asopressin.
Treatment of the acyloctapeptide (173 mg, 0.111 mmol) as described in Example 3 (a) yielded the analog (66 mg, S2.5%) Rf(E) 0.19, Rf(F) 0.43.
[~ D -58.7 (C 0.5, lM AcOH).
~ mino acid analysis: Tyr, 0.96; Phe, 0.98;
Glu, l.Ql; Asp, 1.01; Pro, 1..05; Gly, 1.00, NH3, 2.95. Analysis following performic acid oxidation prior to hydrolysis gave a Cys(03H)-Gly ratio of 1.01:1.00.

('5~7 EX~MPLE 5 ~ -Mercapto~ cyclopentamethylenepropionic aci~), 2-(0-alkyl~tyrosine, ~-valine]-(L- a~lcl D_)-arginine vasopressin.
Compounds of this series were prepared by solid-phase synthesis, modified as in Manning et al., J. Med. Ch~m., vol. 16 (1973) at 975 and Krus~ynski et al. r J. Med. hem., vol. 23 (1980) at 364, to obtain protected intermediates for each analog. The procedures of Bodanszky et al., J. ~m. Chem. Soc., vol. 81 (1959) at 5688 and _ __ _ _ J. Org. Chem., vol. 39 (1974) at 44~, employing a p-nitrophenyl ester, facilitated by the use of hydroxybenzotriazole (Konig et al., supra), were used for the coupling of ~-(5-benzylmeecapto-~, ~-cycloperltamethylenepropionic acid in accordance with Nestor, supra, to obtain precursor compounds.
Each precuxsor was deblocked (duVigneaud, _u~ra) with sodi~lm in liquia ammonia. The resulting disulfhydryl compounds were oxidatively cyclized with potassium ferricyanide (llope et al., sl~ra).
The analogs were desalted and purified by gel filtration on Sephadex G-15 by a two step procedure using 50~ acetic acid and 0.2M acetic acid, respectively, as eluants. The purity and identity of each analog was ascertained by thin-layer chromatography in three different solvent systems, Kruszynski et al., J. Med _hem., vol. 23 (1980~ at 364, and by amino acid analysis as above.
Boc-Phe-Val-Asn-CystBzl)-Pro-D-Arg(Tos)-Gly-resin Boc-Gly-resin (1.562 g, 1.0 mmol, of Gly) was subjected to six cycles of deprotection, neutralization, and coupling to yield the protected heptapeptidyl resin A
35 (2.52Z g, 1.0 mmol).

5~7 2~

soc-Phe-Val-~sn-Cys(Bzl)-Pro-~rg(Tos)-Gly-resin The protected heptapeptidyl resin 13 (2.522 g, 1.0 mmol) was prepared from 1.562 g (1.0 mmol) of Boc-Gly-res.in using solid-phase methodology.
Boc-Tyr(Me)-Phe-Val-~sn-Cys(Bzl)-Pro-D-~rg(Tos)-Gly-resin A single cycle oL solid-phase pept.ide synthesis with Boc-Tyr(Me) as the carboxy component converted heptapeptidyl r~sin ~ (1.261 g, 0.5 mmol) to the corresponding tert-butyloxycarbonyloctapepti~yl resin C (1.35 g, 0.5 mmol).
Boc-Tyr(Et)-Phe-Val-~sn-Cys~Bzl)-Pro-D-~rg(Tos-Gly-resin The heptapeptidyl resin ~ (1.261 g, 0.5 mmol) yielded the tert-butyloxycarbonyloctapeptidyl resirl D (1.357 g, 0.5 mmol) in one cycle of solid-phase peptide synthesis with Boc-Tyr(Et) as the carboxy component.
Boc-Tyr(Me)-PIle-Val-~sn-Cys(Bzl)-Pro-~rg(Tos)-Gly-resin The heptapeptidyl resin B (1.261 gr 0.5 mmo.U was converted to protected octapeptidyl resin E (1.35 g, 0.5 mmol) in one cycle of deprotection, neutralization and coupling with Boc-Tyr(Me).
~ (S-Benzylmercapto)~ ~cyclopentamethylenepropiony-Tyr(F.t)-Phe-Val-~sn-Cys(Bzl)-Pro ~rg(Tos)-Gly-resin The heptapeptidyl resin B (1.261 g, 0.5 mmol) was converted to the ~cyloctapeptide resin tl.43 g, 0.5 mmol) in two cycles of solid pha~e peptide synthesis using as the carboxy component, respectively: Boc-Tyr(Et) and p-nitrophenyl ~-(S-~enzylmercapto)-~, ~ -cyclopentamethylen-propionate.
~oc-Tyr(Me)-Phe-Val-Asn-Cys(Bzl)-Pro-D-~r~ (Tos) -Gly-NH~
The protected oc-tapeptide resin C (1.35 g, 0.5 mmol) was ammonolyæed and the product extracted with warm DMF.
The product was precipitated by addition of water. The crude product was reprecipitated from DMF-ethanol-ethyl ether to give the pure product as a white powder (0.581 g, 88.52% based on initial Gly content o~ the resin) mp.
239-240C; [~]D = -14.9 (C = 1, DMF); Rf(~), 0.54, R (D) 0.73; ~na~- (CS3H85Nl3Ol4S2) ~2~`~()S~7 Amino acid anal~sis: Tyr, 1.02; Phe, 0.98;
Val, 1.02; ~sp, 1.00; Cy~(Bzl), 0.98; ~ro, 1.01;
Arg, 0.97; Gl~, 1.00; N~13, 2.1.
Boc-Tyr(Et)-Phe-Val-~sn-Cys~Bzl)-Pro-D-Arg(Tos~Gly-NI-I2 Treatment of the protected octapeptide resin D (1.357 g, O.5 mmol) a~ above yielded the Boc-octap~ptideamide (0.535 g, 80.69~ based on initial Gly content of the resinj mp. 211-213 C; 1O~D = -16.4 (C = 1, DMF);
R (E) 0 61 R (D), 0.83: Anal. (C6~H87N13Ot~ 2 Amino acid analysis: Tyr, 0.99; Phe, 1.00; Val, 1.01 ~sp, 1.02; cys(nzl), O.9R, Pro, 1.00 Arg, 0.98;
Gly, 1.00; N~13, 213.
~oc-Tyr(Me)-Phe-Val-~sn-Cys(nzl)-Pro-Arg(To~tGly-NH2 Treatment of the protected octapeptide re~sin F (1.35 g, lS 0.5 mmol) as a~ove gave the correspondin~
Boc-octapeptideam.ide (0.S97 g, 90.96~ basecl on initial Gly content Or the resin). mp. 216-217 C (c]ecomp. );
1~]D = -34.82 (C = 1, DMF); Rf(E), 0.S4, Rf(D), 0.73;
Anal. (C63~85N13014S2) Amino ~cid analysis: Tyr, 0.99; Phe, 1.00; Val, 1.02; Asp, 1.01; Cys(B~l), 0.98; Pro, 1.01, ~rg, 0.98;
Gly, 1.00; Nl13, 2.09.
~-(S-Benzylmercapto-~, ~ -cyclopentamethylenepropionyl-Tyr(Et)-Phe-Val-Asn-Cys(Bzl)-Pro-Arq('l'os)-Gly-NH2 The protected acyloctapeptide resin (1.43 gr O.S mmol) was ammonoly~ed and the product extracted w.ith warm DM~. The product was precipltate~ by addition of water.
The crude product was reprecipitated from DMF-ethanol-ethyl ether to give the pure product. (0.490 g, ~6.S4~ based on initial Gly content of the resin).
mp. 211-213 C; ['~D 4 = -39.8 (C =1, DMF); Rf(E), 0-59, Rf(D), 0.75; Anal. (C74H97Nl3Ol3S3) C, H, N-Amino acid analysis: Tyr, 0.99; Phe, 1.01; Val, ~ ; Asp, 1.01; Cys(B~l), 0.99; Pro, 1.02; Arg, 0.98;
Gly, 1.00; NH3, 2.07.

~-(S~Ben7.ylmercapto)~ cycl~pentamethylenepropionyl-Tyr(Me)-phe-val-~sn-cys(Rzl)-pro-D-~r~(Tos)Gly-NJl2 The tert-butyloxycarbonyloctapeptide amide prepared above (0 270 gr 0.206 mmol) wa~ dissolved in TF~
(3 ml) and allowed to stand at room temperature for 20 min. Cold ethex was added. The precipitated material was filtexed and washed with eth~r (5 x 10 ml). The p~oduct was dried in vacuo over sodium hydroxide pellets.
This material (250 mg) was dissolved in DMF (0.8 ml) to which solution N-methylmorpholine was added to give a ~olution of pH 7-Q (moist p~l paper). l`h~ neutralized solution was stirred at room temperature or 20 min.
solution of p-nitrophenyl ~-(S-ben7ylmercapto-~, ~-cyclopentamethylenepropionate (0.135 g, 0.37 mmol) and N-hydroxybenzotri~%ole monohyclrate (57 mq, 0.37 mmol) in DMF (1.0 ml) w~s nddcd. The reaction mixture was stirred at room temperature overnight and TLC (system E) showed that the reaction was complete. Methanol (80 ml) and ether (20 ml) were added with vigorou~
mixing. The precipitated material was filtered, washed with a mixture of methanol-ether (8:2), and clried ln acuo. ~he crude product (270 mg) was reprecipitated orm DMF-methanol to give the acyl pepticle amide (263 mg, 75.2~); Mp. 220-221 C: ~)D = -25.7 (C - 1, DMF);
Rf(E), 0.55, R~D), 0.83: ~nal. (C73H95Nl3Ol3S3) C, H, N.
~mino ~cid analys.is: Tyr, 0.98; Phe, 1.01; Val, 1.02 Asp, 1.02; Cy~(Bzl), 0.97; Pro, 1.03; ~rg, 1.0; Gly, 1.00;
NH3, 2.06.
~-(S-Benzylmercapto-~ cyclopentamethylenepropionyl-Tyr(Et)-Phe-Val-~sn-Cys(~zl)-Pro-D-~rg(Tos)-Gly-NII2 l'he tert-butyloxycarbonyloctapeptide amicle (0.398 9, O.3 mmol) was deprotected and coupled with p-nitrophenyl ~-(S-benzylmercapto)-~, ~-cyclopentamethylenepropionate (0.232 g, 0.6 mmol) as described above to give the acyloctapeptide amicle ~0.361 g, 81.67~) mp. 222-22~" C;
1~]D = -22.8D (C = 0.5, DMF); R~(E), 0.5, Rf(D), 0.83;
~nal. (C7~ll97Nl3Ol3s3) ~ mino acid analysis: Tyr, 1.0; Phe, 1.02; Val, 1.03; ~sp, 1.02; Cys(B~.l), 0.98; Pro, 1.03; ~rg, 0.99;
Gly, 1.00; Nl13, 2.11.
~ (S-~en~.ylmercapto)~ cyclopentamethylenepropionyl-Tyr(Me)-Phe-Val-~sn-Cys(Bzl)-Pro-~rg(l'os)-Gly-NII2 Tert-8utyloxycarbonyloctapeptide amide (0.~94 g, 0.3 mmol) was cleprotected and coupled with p-nitrophenyl ~-(S-benzylmercapto)-~ cyclopentamethylenepropionate (0.232 q, 0.6 mmol) as above to produce the acyloctapeptide amide (0.38~ g, 8~.65~); mp. 211-214 C;
~D 1 = -39.2 (C = 1, DMF); Rf(E), 0.~7, ~f(D), O.R5;
Anal- (C73~lgsNl30l3 3 ~ mino acid analysis: Tyr, 0.99; Phe, 1.02; Val, 1.03; ~sp, 1.01; Cys(l~.l), 0.99; Pro, 1.02; ~rc~, 0.9~;
Gly, 1.00; N~3, 2.04.
[l-(~-Mercapto~ -c~clopentamethylenepropionic acid), 2-(0-ethyl)tyrosine, ~-valine]-arqinine vasopressin solution of protected acylocta-peptide amide (1~0 mg, 0.095 mmol) in 400 ml of ammonia (dried and xedistilled from sodium) was st.trred and treated at the boiling point with sodium from a stick of the metal contained in a small-bore glass tube until a light blue color persisted in the solution for 30 s. Dry glacial acetic acid (0.4 ml) was added to discharge the color. The solution was evaporated by passing N2 through the flask. ~fter 5 min, the residue was dissolved in aqueous acetic acid (10~, 50 ml) to wh~ch was added 800 ml of water.
The solution was treated with 2M ammonium hydroxide solution to give a solut~on of pH-6.5. ~n excess of a solution of potassium ferricyanide (O.OlM, 16 ml) was added gradually with stirring. The yellow solution was stirred for 10 min more and for 10 min with anion exchange resin (~io-Rad ~G-3, Cl form, 10 g damp weight). The suspension was slowly filterecl through a bed of resin ~50 9 damp weight). ~fter washing the bed with aqueous acetic acid (0.2~, 200 ml), the combinecl ~t.~(~5~7 2~

filtrate and wa~hings were lyophyli~ed. The resulting powder (1.63 g) wa~ desalted on a Sephadex G-15 column 1110 x 2.7 cm) by elution with aqueous acetic acid (50~) at a flow rate 5 ml/h. The eluate was fraction~ted and monitored or absorb~nce o~ 280 nm. The fractions comprising the major peak were pooled an~l lyophylized.
The residue (28 mg) wa~ subjected to gel filtration on a Sephadex G-1~ column (100 x 1.5 cm). Product was eluted with aqueous acetlc acid ~0.2M) at a flow rate of ~ ml/h.
The peptide was eluted in a slngle peak (absorbancr2 280 nm). Lyophyli7.ation of the pertinent fractlons yielded the vasopressin analog (2~ mg, 20.6~). TL,C
Rf(E), 0.31, Rf(F), 0.62, [~]D = -65.1 (C = 0.2, lM
I\cO~I ) .
Amino acid analysis: Tyr, 1.00; Phe, 1.01; Val, 1.01, Asp, ].01; Pro, l.Ol;~rg, 1.00; Gly, 1.00; N~13, 1.97. ~nalysis ollowing performic acid oxidation prior to hydrolysis gave a Cys (03H)-Gly ratio of 1.01:
1 .00.
[~ -Mercapto-p~ -cyclopentamethylene~ropionic ~cid], 2-(0-methyl)tyroslne, 4-valine, 8-1)-arginille] vasopressin The peptide intermediate (168 mg, 0.115 mniol) was reduced ~y sodium in liquid ammonia, reoxidize~1, deionized, and purified as above to give 49.5 mg o product (35.5~) Rf(E), 0.30, Rf(F), 0.61; [~]D = -~6.~1 (C - 0.~, lM
~cOH).
Amino acid analysis: Tyr, 0.98: Phe, 1.01; Val, 0.98; ~sp, 0.99; Pro, 1.03; ~rg, 0.98; Gly, 1.00; NH3, 12.1. ~nalysis following performic acid oxidation prior to hydrolysis gave a Cys(03H)-Gly ratio 1.03:1.00.
[l-(~-Mercapto-~, ~-cyclopentamethylenepxopionic acid), 2-(0-ethyl)tyrosine, 4 valine, 8-D-arginine] vasopressin ~he yield of analog from 167 mg (0.113 mmol) of inter-mediate was 29 mg (20.9~). Rf(E), 0.29, Rf(F), 0.57, [~JD = -41.1 (C = 0.3, lM ~cOH).

Q5~7 ~ mino acid analysis: Tyr, 0.98; Phe, 1.01; Val, 1.03; ~sp, n.g9; Pro, 1.03: ~rg, 1.02 Gly, 1.00 N1~3, 1.98. ~nalysis following performic ac.id oxidation prior to hydrolysis gave a Cys ~O3l~)-Gly ratio 1.01:
1.00.
~ -Mercapto-~,~ -cyclopentamethylenepropionic acid~, 2-(O-methyl)tyrosine, ~-valine]-arqinine vasopressin Treatmen~ of the acyl octapeptide (174 mg, 0.119 mmol) as above yielded the 51.5 mg of prod~ct (35.6~).
RftE), 0.28, Rf(F), 0.60; [~]D = -66.3 (C = 0.4, lM
~cO~I ) .
~mino acicl analysis: Tyr, 0.99; Phe, 1.01; Val, 1.02; ~sp, 1.01; Pro, 1.00; ~rg, 1.01; Gly, 1.00; N~13, 2.11. ~nalysis followinc3 perform.ic acid oxiclation prior to hydrolysis g~ve a Cys(O3ll)-~ly ratio ].. 03:1.00.
EX~MPLE 6 [l-(~-Mercapto~ -cyclopentamethylenepropionic acid), 2-(O-ethyl)tyrosLle, 4-valine, 7-(3,~-dellydroproline)~
arginine vas~pressin The compound was prepared as i.n Example 5, using ~3-proline instead of proline.
EX~MPLE 7 ~ ercapto-~,~-cyclopentamethvlenepropionic acid), 2-substituted, ~-valine, 7-proline~ -(L- and D-) arginine vasopressin Compounds of this series ~ere preparec1 as in Example 5. Purity was determined by TLC assay on silica gel in ~two solvent systems: E. butanol/acetic acicl/water (B~W) (4:1:5) or F. butanol/acetic acicl/water/pyridine 3~ (15:3:3:10). Results were:

()5~

X Z l~f ~ l~f ~;~
__ _ _. _ D-Tyr L-~rg O.:L 7 O. r~o D-~he L-~rg 0.1 7 0 r~
Gly L-~rg0.15 0.~
D-~la L-~rg O.l6 0.~9 D-Val L-~rg 0.17 0.49 D-Leu L-~rg 0.17 0.53 ~-lle L-~rg0.17 0.51 D-~rg L-~rg 0.0~ 0.30 D-Phe ~-~r~ O.l~i 0.51 ~X~MPLE 8 Antagonism to the vasopressor response was estima~ed in accordance with Dyckes et al., J. Med. Chem., vol. 17 ~1974) at 969~ The values are expressed as P~2 values, defined by Schild et al.~ Br. J. Pllarmacol., vol. 2 (1~7) ~t 1~9.
~ ctivity as antidiuretic agoni.sts was determined by intravenous injection of compounds being evaluated into ethanol-anestlles.ized water-loadecl rats in accordance 2~ witll Sawyer et al., Endocrinology, vol~ 63 (1958) at 694.
~ ntagonistic potencies were determined and expressed as "effective doses" and as P~2 values. The "efectlve dose" is deined as the dose (in nanomoles per kilo~ram) that reduces the response seen from 2x units o agonist injected 20 min after the dose of antagonist to the response with lx units of agonist. Estimated in _ lVO
"P~2~ values represent the negative loga~ithms o~ the effective doses divided by the estimated volume of distribution ~67 mL/kg). Results are given in Table r.

~a'~0s~7 ,~ o ~ I_ I )U~ o o o o h tJl~) o ~-1 ~ o o o +1 ~ +~+~ o t I ~
d' Or~ 1 0 In ~
o ~ ~ o c~ ~ o ~n ~n ,1 ~Io~r~ o o o o l~J
~ ~ o o o r~ o o o ~n ~
~d n~ +1 +1 ~r V O ~ ~ O co ~0 C C~
~ ~ . . . . . t,-~ .
rS r~ r~
~I h h rlr~1 ~ t~) b' a~ ~I h h w ~ ,~ a n C~ ~ , a) a) r~ h h $-1 h ~I h h h ~E~ E~ E-l E~ t~ t~ t-~ E~
Il) Cr ~ U t~ r~l rJ r~
r~
~ I
r~ r,~

r a~
r~
a a) t-~

,~ ~n, > ~ p ~ h ;~
.a Q, ~ ~ rJ ~ r ) ~ t I r ~ ~ ~ r-~ ~' 'r~, -~ t ~ r t~ , r~ rt3 ~r~ d ~U ~d ~r~ 5~7 3~

Results displayed in Table I show that eompounds of this invention, particularly [l-(~-mere~pto-~cyelopentamethylenepropionie ae.id), 8-nrginine] vasopressin and ~ mercapto-~,~ -eyclopentamethylellepropionic acid), 2-(0-methyl)tyrosine, 8-argin.ine] vasopr~ssin antagonize tne vasopressor response to argi.nine va~sopressin and also exhibit a marked reduetion in alltid.iuretie activity.
EX~MPLE 9 3~ ~l-(B-Mereapto~ ,~-eyelopentamethylenepl-opioni.e aeid), 2-(0-alkyl)tyrosine, 4-vali.ne, ~-(],- anc.l ~-) arginine] vasopressin compounds, eva].l.~ated as in Example 8I were weak antidiuretic agonists. They eaused an initial submaximal inhib.il:ion of urine 10w lasting about 10 min, followecl by a per.iocl of inhibition of respons.es to ADII lastitlg 1 to 3 h, depending on the dose. This inhibition was reversible, that is, eould be overcome by raising the dose of ADIT. Repeated assays permitted estimation 2~ of the "effeetive dose" of eaeh analog, whieh is de-fined as the dose whieh reduees the ~ntidiuretie response to 2x units of ~DII injeeted 20 min after the dose of antagonist to eqùal the response to lx units injeeted prior to the antagollist. 'I'he estimated effeetive doses for these analoc3s /in nmoles/kg) and antivasopressor activity are given in Table ~I.
Whereas [l-(~-mereapto-~ eyclopentamethylenepro-ptonie acid), 2-(0-alkyl)tyrosine, ~-valine, ~-(.T,- and D-) 3n arginine] vaso~ressin compouncls were weak ~nt:id;-lretic a~onists, cnusincl an i.nltial submax;.m~l in~llbit.ion of urine flow lasting about 10 min, followed by a period of inhibit.ion of responses to ADH lastinc3 1 to 3 h, the preferred compounds of this invention, indicated by asterisks in the table below, had no antidluretic agonistic aetivity.

~;J
:: .
Table II
~nti-~rtidiuretic ~ntivaso~ressor ED PA2 ED pA2 C~?~und n~ol~s/K~ r.r~les/Xg d(CH2)5 D-Tyr VAVP 2.2 +0.27.51+0.08(4) 0.29T0.098.41+0.11(4) d(CH2)5 ~-P~e ~iA~ 0.67+0.13*8.07+0.09(8)0.58+0.048.05+0.03(4) d(CH2)5[Gly ~'tr~VP agonist - a~onist d(CH2)5~D-~la ]VA'IP agonist - 177 T31 5.79+0.08(4) d(CH2~5[~-Val jVAVP 2.3 +0.3 * 7.48+0.06(4) 27 T3 6.41+0.05(4) d(CE2)5[~-reu ]V~VP 1.2 +0.3 * 7.79T0.12(4) 26 '5 6.45+0.09(4) ~ ~
d(CH2)5~D-Ile2~VA~rP 0.70+Q.0 * 7.38+0.05(4) 8.2 T1.4 6.94iO.08(5) Y
d(CH2)5[D-~rg jV~v~ ~39 ~5.9 rV 260 ~v 5.4 Gn d(CH2)5 D-P~e V~A~ 6.9 +1.37,01fO.10~9) 0.73 7.93 T 0.07(4) d(CH2)5Tyr(:'e)~,~AVP 15 +3 6.68T0.11(~) 0.28+0.05 3.4~ 0.07(~) d(CH2)5~yr(~t)VD~.~YrP 5.7 +0.5 '.lC 0.08(4) n.34 0.0 8.31-0-~5~3) . .

.
.~

s"

Table II(Continued) Anti-a~ti~iuretic Antivas~pressor Co~o~nd E ?A2 _ 2 d(C~2)5Tyr(i-Pr)VDAVP 8.5 0.C7 6.88-0.07(4) 0.28TO.Q7 8.41T0.08 (8) d(cH2)5Tyr(n-pr)vDAvp 14~2 6.67+0.05(4) 1.1~0.2 7.86~^.10 (8) d(cH2)5Tyr(L~l2)vAvp 3.1'0.4 7.35+0.06(4) 0.29+0.06 8.32T0.08(4) w d(C;~2)5Tyr(Et)VAV~ 1.9~0.2 7.57T0.06(4) 0.49+0.11 8.16+0.09(4) N
d(Cri2)5Tyr(i-Pr)Vr.VP 3.6+0.9 7.32+G.06(6) 0.31+0.06 8.36+0.09(4) d(CH2)5Tyr(~-2r)VAVP 3.5-0.06 7.29TO.07(4) 0.40~0.04 8.22+0.04(4) 67 d(CH2)~-D--yr(~e)VAVP 1.2-0.3 7,77+Q.07(6) 0.23fo.04 8.48+Q.08(4) d(CF.2)5-D--yr( r t)VAVP 1.1~0.2 7.81+0.07(5) 0.45f0.11 8.22 0.12(4) d(C~2)5~TYr~Et)~V~
~3 Pro7 A~7P 1. 5TO . 3 ~2Q(~4 :7 The preEerred compounds of this invention are ~lso more select.ive than prior art antidiurctic ant~gonists with respect to antivasopressor potencies, as shown by the ratios of antivasopressor/anti-antidiuretic effective doses:
, ~nt.ivasopressor Compounds ED s ~n~i-.tn~i~liur~tic d(Cil2)5 D-Tyr(Et) V~vP 0.41 d(CI~ ) D-r~ V~VP 0. n7 d(Cll2)5[D-Val2]V~VP 12 d(Cll2)5 [D-Leu ~ V~VP 22 d(CI12)5[D~ ]V~Vp 12 F.X~MPLE 1~
(a) ~ntagonism to ~ -mercapto-~,~-cyclopenta-methylenepropionic acic~), 2-(0-alkyl)tyrosine, ~-vaJille]-(L- and D-)-ar~ine vasopressin compounds to en~o~enous ADI~ was shown by injection of the compound intraperitoneally .into conscious rats. Urine was collected for 4 h after the injections. l`he data in the Table below are the means ~ SE of 2~ results on groups of 4-6 rat~. *P <0.05 and **P ~0.005 are given for d.iferences between the means for rats receiving antagonists and the means for reponses of the same rats injected with solvent only. The mean control urine volume .rate for ~olvent-injected r~ts was 0.9 + 0.1 ml/kg per hr and the mean osmolality was 15~4 + 85 mOsm/kgll20 (n=32~.

54~7 Dose Ur~ne volume Osmolality ug/kg ml/kg per hr m~sm/kgll2o d(Cll2)5~yr(Me)100 1.5 + 0.313~1 ~ 428 V~7~VP
300 ~.2 ~ 0.4* 961 ~ 20~*
d(CH2)5Tyr(Et)- 30 2.8 ~ 0.~** 6~0 -t 47 VD~VP
100 9.5 ~ *23~ ~ 25**
d(Cll2)5Tyr(Me)- 10 1.1 + 0.5 1303 ~ 190 1 ~Vl\VP
3.4 ~ 0.9~ 51~ ~ 105~
d(CIi2)5T~r(~t)- 10 7.~ + 1.0~ 3lfi + 38~*
. Vir\VP
13.~ + 2.5~ 194 ~ 17*~
tb) Responses by intact female rats, weighincJ
20~ to ~ .J, to llltl-~t?e~lto~ je~ )t d(C112)5Tyr(Et)V~VI' were determined in ~ block design experiment in which each rat received solvent and both doses of the ~DII antagon.ist. Injections were ?~ given at l~ast two days apart. The rats were on water ad lib. Injections we.re m~de at 11 ~.m., ~fter which spontaneously vo.icled urine was collected hourly Eor four hours.
In ~ig. 1 i.s shown os~ol.~li.ty Or tllt. ~lrinc~
~s a ~uncti.on Or t.imc. tJrine osmol~]i.tics for the control (solvcnt-injecttcl) were .lvcr.lrlcrl ovcr 2 hour l~criods owin(l to infrc(lucl)cy ol l.ll~in-ltiOIl.
In lir~. 2 i~ shown tllc urinc ollt.l~uL ns a function of time.
3~ In l)oth lirlurcs, vcrtic.~l ].inc~s tllrou~ ?oints indic.~tc Sl's.

Compounds wherein Tyr at the 2-position is of the D-series and is unetherified (X' is H) are pre-pared as in Examples 1-5. The compound in which Z-is L-Arg is very active as an antagonist of the anti-diuretic activity of arginine vasopressin.
The preceding examples can be repeated with similar success by substituting the generically or specifically described reactants and/or operating conditions of this invention for those used in the preceding examples.
From the foregoing description, one skilled in the art can easily ascertain the essential characteristics of this invention and, without departing from the spirit and scope thereof, can make various chan~es and modifications of the invention to adapt it to various usages and conditions

Claims (4)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A process for the production of a compound of the formula wherein Tyr is D-Tyr and Z is D- or L-Arg, which comprises the steps of:
(a) treating Boc-Gly-resin by solid phase synthesis by six cycles of deprotection, neutralization and coupling with a selected amino acid to produce a corresponding pro-tected heptapeptidyl resin of the formula Boc-Phe-Val-Asn-Cy(Bzl)-Pro-Z(Tos)-Gly-resin, wherein Z is as above;
(b) treating the corresponding protected heptapeptidyl resin produced in step (a) by solid phase peptide synthesis in a cycle of deprotection, neutralization and coupling with Boc-D-Tyr(H) to produce a corresponding tert-butoxycarbonyl-octapeptidyl resin of the formula Boc-D-Tyr(H)-Phe-Val-Asn-Cy(Bzl)-Pro-Z(Tos)-Gly-resin, wherein Z is as above;
(c) ammonolyzing the corresponding protected octapep-tidyl resin produced in step (c) to a corresponding Boc-octapeptidyl amide of the formula Boc-D-Tyr(H)-Phe-Val-Asn-Cy(Bzl)-Pro-Z(Tos)Gly-NH2;
(d), converting the corresponding Boc-octapeptide amide produced in step (c) to a corresponding .beta.-(S-benzylmercapto) .beta.,.beta.-cyclopentamethylenepropionyl-octapeptide amide of the formula by coupling a neutralized, deprotected solution of a correspond-ing tert-butoxycarbonyl-octapeptide amide with p-nitrophenyl-.beta.
-(S-benzylmereapto)-.beta.,.beta. cyclopentamethylene propionate, in the presenee of N-hydroxybenzotriazole monohydrate and (e) reducing a corresponding .beta.-(S-benzylmercapto)-.beta.,.beta.-cyclopentamethylenepropionyloctapeptide amide produced in step (d) with sodium in liquid ammonia and oxidatively cyclizing a resulting disulfhydryl compound with potassium ferricyanide.

2. A process according to claim 1, wherein Z is L-Arg.

3. A compound of the formula wherein Tyr is D-Tyr and Z is D- or L-Arg, whenever produced by the process claimed in claim 1, or by an obvious chemical equivalent thereof.

4. A compound according to claim 3, wherein Z is L-Arg, whenever produced by the process claimed in claim 2, or by an obvious chemical equivalent thereof.