CN108947981B - 3R-indolylmethyl-6S-aliphatic amino acid modified piperazine-2, 5-dione, and synthesis, activity and application thereof - Google Patents

3R-indolylmethyl-6S-aliphatic amino acid modified piperazine-2, 5-dione, and synthesis, activity and application thereof Download PDF

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CN108947981B
CN108947981B CN201710393398.3A CN201710393398A CN108947981B CN 108947981 B CN108947981 B CN 108947981B CN 201710393398 A CN201710393398 A CN 201710393398A CN 108947981 B CN108947981 B CN 108947981B
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赵明
彭师奇
王玉记
吴建辉
张可欣
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Capital Medical University
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    • C07D403/02Heterocyclic compounds containing two or more hetero rings, having nitrogen atoms as the only ring hetero atoms, not provided for by group C07D401/00 containing two hetero rings
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Abstract

The invention discloses a 3R-indolylmethyl-6S-fatty amino acid modified piperazine-2, 5-dione, and synthesis, activity and application thereof, and discloses (3R,6S) -3- (AA-amino-n-hexanoylamino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione (wherein AA is an L-Ala residue, a Gly residue, an L-IIe residue, an L-Leu residue and an L-Val residue). Discloses a preparation method thereof, discloses the anti-tumor metastasis activity thereof and the anti-inflammatory activity thereof, and thus discloses the application thereof in preparing anti-tumor metastasis medicaments and anti-inflammatory medicaments.
Figure DDA0001308032380000011

Description

3R-indolylmethyl-6S-aliphatic amino acid modified piperazine-2, 5-dione, and synthesis, activity and application thereof
Technical Field
The invention relates to (3R,6S) -3- (AA-amino-n-hexanoylamino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione. To a process for their preparation, to their anti-tumor metastatic activity, and to their anti-inflammatory activity, and to their use in anti-tumor metastatic and anti-inflammatory drugs. The invention belongs to the field of biological medicine.
Background
Tumors seriously threaten the health of human beings. In addition to the poor prognosis of patients with tumors by themselves, metastasis associated with tumors further worsens the prognosis of patients. For example, more than 90% of patients with tumors die from metastases. Because the existing antitumor drugs have no effect of resisting tumor metastasis, the clinical curative effect of tumor chemotherapy is not ideal. The invention relates to a medicament for resisting tumor metastasis, which is an urgent clinical need. The inventors have previously disclosed that diketopiperazines of the four S, S-, R, R-, R, S-and S, R-configurations inhibit migration and invasion of HCCLM3 (highly metastatic human liver cancer cells) at a concentration of 0.5. mu.M. Later, the inventors further disclosed that R, R-configured diketopiperazines inhibited tumor metastasis to the lung in C57BL/6 mice at a dose of 5. mu. mol/kg. However, the lowest effective dose is 5. mu. mol/kg. To reduce the minimum effective dose, the inventors have developed various modifications to the amino n-butyl group of the diketopiperazine in the S, R-configuration. After 3 years of exploration, it was found that acylation of the amino n-butyl group of the S, R-diketopiperazine with amino n-hexanoic acid acylated with amino acids having aliphatic side chains (L-Ala, Gly, L-IIe, L-Leu and L-Val) not only reduced the minimum effective dose against tumor metastasis to 0.5. mu. mol/kg, but also reduced the minimum effective dose against inflammation to 0.5. mu. mol/kg. Because the toxic and side effects of the medicine can disappear along with the reduction of the dosage, the reduction of the effective dosage by 10 times shows that the structure modification has outstanding technical effect. Based on these findings, the inventors have proposed the present invention.
Disclosure of Invention
The first aspect of the present invention provides (3R,6S) -3- (AA-amino-n-hexanoylamino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione of the formula (wherein AA is a L-Ala residue, a Gly residue, a L-IIe residue, a L-Leu residue and a L-Val residue).
Figure GDA0002419745560000011
The second aspect of the present invention provides a method for synthesizing (3R,6S) -3- (AA-amino-n-hexanoylamino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione (wherein AA is L-Ala residue, Gly residue, L-IIe residue, L-Leu residue and L-Val residue), which comprises:
(1) D-Boc-Lys (Cbz) and L-Trp-OBzl are condensed to obtain D-Boc-Lys (Cbz) -L-Trp-OBzl;
(2) removing Boc from D-Boc-Lys (Cbz) -L-Trp-OBzl in ethyl acetate solution of hydrogen chloride to obtain D-Lys (Cbz) -L-Trp-OBzl;
(3) cyclizing D-Lys (Cbz) -L-Trp-OBzl in a saturated ethyl acetate solution of a 5% sodium bicarbonate water solution to obtain (3R,6S) -3- (benzyloxycarbonylamino n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione (1);
(4) the compound 1 is subjected to hydrogenolysis to remove benzyloxycarbonyl to obtain (3R,6S) -3- (amino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-diketone (2);
(5) condensing amino-n-hexanoic acid methyl ester with Cbz-AA (AA is L-Ala residue, Gly residue, L-IIe residue, L-Leu residue and L-Val residue) to obtain Cbz-AA-amino-n-hexanoic acid methyl ester (3 a-e);
(6) saponifying and removing methyl ester from compound 3a-e to obtain Cbz-AA-amino n-hexanoic acid (4a-e) (wherein AA is L-Ala residue, Gly residue, L-IIe residue, L-Leu residue and L-Val residue);
(7) condensing the compound 2 and the compound 4a-e to obtain (3R,6S) -3- (Cbz-AA-amino n-hexanoylamino n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-diketone (5a-e) (wherein AA is L-Ala residue, Gly residue, L-IIe residue, L-Leu residue and L-Val residue).
(8) The compound 5a-e is subjected to hydrogenolysis to remove the benzyloxycarbonyl group to obtain (3R,6S) -3- (AA-amino-n-hexanoylamino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione (6a-e) (wherein AA is an L-Ala residue, a Gly residue, an L-IIe residue, an L-Leu residue and an L-Val residue).
In a third aspect of the present invention, (3R,6S) -3- (AA-amino-n-hexanoylamino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione (wherein AA is L-Ala residue, Gly residue, L-IIe residue, L-Leu residue and L-Val residue) was evaluated for its activity in inhibiting the metastasis of lung cancer in C57BL/6 mice.
The fourth aspect of the present invention is to evaluate the inhibitory effect of (3R,6S) -3- (AA-amino-n-hexanoylamino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione (wherein AA is L-Ala residue, Gly residue, L-IIe residue, L-Leu residue and L-Val residue) on the inflammation of ICR mice.
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FIG. 1 is a scheme for the synthesis of (3R,6S) -3- (AA-amino-n-hexanoylamino) -6- (indole-3-methyl) -piperazine-2, 5-dione (6a-e) AA in 3a-6a is the L-Ala residue; AA in 3b-6b is Gly residue; AA in 3c-6c is L-Ile residue; AA in 3d-6d is L-Leu residue; 3e-6e, wherein AA is a L-Val residue, i) Dicyclohexylcarbodiimide (DCC), 1-hydroxybenzotriazole (HOBt) and N-methylmorpholine (NMM); ii) a solution of hydrogen chloride in ethyl acetate; iii) ethyl acetate, 5% aqueous sodium bicarbonate; iv) Pd/C, H2(ii) a v) methanol, NaOH (2M).
Detailed Description
To further illustrate the invention, a series of examples are given below. These examples are purely illustrative and are intended to be a detailed description of the invention only and should not be taken as limiting the invention.
EXAMPLE 1 preparation of D-Boc-Lys (Cbz) -L-Trp-OBzl
To a solution of 1.90g (5.0mmol) of D-Boc-Lys (Cbz) and 20mL of dried Tetrahydrofuran (THF) were added 0.68g (5.0mmol) of 1-hydroxybenzotriazole (HOBt) and 1.24g (6.0mmol) of Dicyclohexylcarbodiimide (DCC) under ice-cooling and stirred for 30 minutes to obtain reaction solution A. 1.47g (5.0mmol) of L-Trp-OBzl was dissolved in 20mL of dry THF, and N-methylmorpholine (NMM) was added to adjust the pH to 9 to obtain reaction solution B. The reaction solution B was added to the reaction solution A and reacted at room temperature for 12 hours, and TLC (methylene chloride/methanol, 40/1) showed completion of the reaction. The reaction mixture was filtered, the filtrate was concentrated under reduced pressure, and the residue was dissolved in 50mL of ethyl acetate. The resulting solution was sequentially saturated NaHCO3Aqueous solution (25 mL. times.3), saturated aqueous NaCl solution (25 mL. times.3), 5% KHSO4Aqueous wash (25 mL. times.3), saturated aqueous NaCl wash (25 mL. times.3), saturated aqueous NaHCO3An aqueous wash (25 mL. times.3) and a saturated aqueous NaCl wash (25 mL. times.3). Anhydrous Na for ethyl acetate layer2SO4Drying for 12 hours. Filtering off Na2SO4The filtrate was concentrated under reduced pressure, and the residue was purified by silica gel column chromatography (dichloromethane/methanol, 40/1) to give 2.94g (90%) of the title compound as a colorless solid. ESI-MS (M/z):657[ M + H]+
EXAMPLE 2 preparation of D-Lys (Cbz) -L-Trp-OBzl
To 2.62g (4.0mmol) of D-Boc-Lys (Cbz) -L-Trp-OBzl was slowly added 30mL of a solution of hydrogen chloride in ethyl acetate (4M) under ice-bath and stirred for 4 hours, TLC (dichloromethane/methanol, 40/1) showed the reaction was complete. The reaction mixture was concentrated under reduced pressure, and the residue was dissolved in 30mL of anhydrous ethyl acetate, and the resulting solution was concentrated under reduced pressure, and the residue was dissolved in 30mL of anhydrous ethyl acetate. This operation was repeated three times. The residue was suspended with 30mL of anhydrous ether by means of a sonicator and after standing the ether was removed to give 2.07g (93%) of the title compound as a yellow powder. ESI-MS (M/z):557[ M + H ]]+
EXAMPLE 3 preparation of (3R,6S) -3- (benzyloxycarbonylamino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione (1)
A solution of 1.95g (3.5mmol) D-Lys (Cbz) -L-Trp-OBzl and 50mL ethyl acetateWith saturated NaHCO3After the aqueous solution was sufficiently washed (25 mL. times.3), the ethyl acetate layer was stirred at 80 ℃ for 56 hours. TLC (dichloromethane/methanol, 20/1) showed the reaction was complete. The reaction mixture was allowed to stand well at room temperature and filtered to give 0.72g (46%) of the title compound as a colorless solid. ESI-MS (M/z):449[ M + H ]]+
EXAMPLE 4 preparation of (3R,6S) -3- (amino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione (2)
To a solution of 0.67g (1.5mmol) of (3R,6S) -3- (benzyloxycarbonylamino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione (1) in 10mL of Dimethylformamide (DMF) was added 0.07g of Pd/C (10%) and the mixture was taken up in H at room temperature2TLC (dichloromethane/methanol, 20/1) showed the reaction was complete for 48 hours. Pd/C was filtered off from the reaction mixture, and the filtrate was concentrated under reduced pressure to give 0.48g (95%) of the title compound as a colorless solid. ESI-MS (M/z) 315[ M + H ]]+
EXAMPLE 5 preparation of amino-n-hexanoic acid methyl ester
5.2mL of thionyl chloride was added dropwise to 52mL of methanol under ice-cooling, stirred for 30 minutes, and 0.26g (2.0mmol) of amino-n-hexanoic acid was added thereto. The reaction mixture was stirred at room temperature for 24 hours. TLC (dichloromethane/methanol, 3/1) showed the reaction was complete. The reaction mixture was concentrated under reduced pressure, the residue was dissolved in 30mL of methanol, and the resulting solution was concentrated under reduced pressure. This operation was repeated three times. The residue was added to 30mL of anhydrous ether and thoroughly suspended by means of a sonicator, and the ether was removed to give 0.27g (94%) of the title compound as a colorless powder. ESI-MS (M/e) 145[ M + H]+
EXAMPLE 6 preparation of Cbz-Ala-amino-n-hexanoic acid methyl ester (3a)
From 0.33g (1.5mmol) Cbz-Ala and 0.22g (1.5mmol) methyl aminohexanoate, 0.47g (90%) of the title compound was obtained as colorless solid by the method of example 1. ESI-MS (M/z):351[ M + H]+
EXAMPLE 7 preparation of Cbz-Gly-amino-n-hexanoic acid methyl ester (3b)
From 0.31g (1.5mmol) Cbz-Gly and 0.22g (1.5mmol) methyl aminohexanoate, 0.46g (91%) of the title compound are obtained as colorless solid by the method of example 1. ESI-MS (M/z):337[ M + H]+
EXAMPLE 8 preparation of Cbz-Ile-amino-n-hexanoic acid methyl ester (3c)
From 0.40g (1.5mmol) Cbz-Ile and 0.22g (1.5mmol) methyl aminohexanoate, 0.52g (88%) of the title compound was obtained as colorless solid by the method of example 1. ESI-MS (M/z) 393[ M + H ]]+
EXAMPLE 9 preparation of Cbz-Leu-amino-n-hexanoic acid methyl ester (3d)
From 0.40g (1.5mmol) Cbz-Leu and 0.22g (1.5mmol) methyl aminohexanoate, 0.54g (92%) of the title compound was obtained as a colorless solid by the method of example 1. ESI-MS (M/z) 393[ M + H ]]+
EXAMPLE 10 preparation of Cbz-Val-amino-n-hexanoic acid methyl ester (3e)
From 0.38g (1.5mmol) Cbz-Val and 0.22g (1.5mmol) methyl aminohexanoate, 0.49g (87%) was obtained as a colorless solid using the method of example 1. ESI-MS (M/z):379[ M + H]+
EXAMPLE 11 preparation of Cbz-Ala-amino-n-hexanoic acid (4a)
0.42g (1.2mmol) Cbz-Ala-amino-n-hexanoic acid methyl ester (3a) was dissolved in 8mL methanol, the pH was adjusted to 12 with aqueous NaOH (2M) on ice, stirred at room temperature for 4 h, and TLC (dichloromethane/methanol, 20/1) showed completion of the reaction. The reaction mixture was saturated with KHSO in ice bath4Adjusting pH of the aqueous solution to 7, concentrating under reduced pressure, and adding saturated KHSO to the aqueous phase4Adjusting pH to 2 with water solution, extracting with 10mL ethyl acetate for three times, washing with 10mL saturated NaCl water solution for three times to make solution pH 7, and adding anhydrous Na2SO4Drying for 12 hours. Filtering to remove Na2SO4The filtrate was concentrated under reduced pressure to give 0.36g (89%) of the title compound as a colorless solid. ESI-MS (M/z):337[ M + H]+
EXAMPLE 12 preparation of Cbz-Gly-amino-n-hexanoic acid (4b)
From 0.40g (1.2mmol) Cbz-Gly-amino-n-hexanoic acid methyl ester (3b) 0.35g (92%) of the title compound are obtained as colorless solid by the method of example 11. ESI-MS (M/z):323[ M + H]+
EXAMPLE 13 preparation of Cbz-Ile-amino-n-hexanoic acid (4c)
From 0.47g (1.2mmol) of Cbz-Ile-amino-n-hexanoic acid methyl ester (3c) gives 0.41g (90%) of the title compound as colorless solid. ESI-MS (M/z):379[ M + H]+
EXAMPLE 14 preparation of Cbz-Leu-amino-n-hexanoic acid (4d)
From 0.47g (1.2mmol) Cbz-Leu-aminon-hexanoic acid methyl ester (3d) 0.42g (93%) of the title compound are obtained as colorless solid by the method of example 11. ESI-MS (M/z):379[ M + H]+
EXAMPLE 15 preparation of Cbz-Val-amino-n-hexanoic acid (4e)
From 0.45g (1.2mmol) Cbz-Val-aminon-hexanoic acid methyl ester (3e) 0.38g (86%) of the title compound are obtained as colorless solid by the method of example 11. ESI-MS (M/z) 365[ M + H]+
EXAMPLE 16 preparation of (3R,6S) -3- (Cbz-Ala-amino-n-hexanoylamino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione (5a)
To a solution of 0.34g (1.0mmol) of Cbz-Ala-amino-n-hexanoic acid (4a) and 5mL of anhydrous DMF was added 0.14g (1.0mmol) of HOBt and 0.25g (1.2mmol) of DCC under ice-bath, and the mixture was stirred for 30 minutes to obtain reaction solution A. 0.31g (1.0mmol) of (3R,6S) -3- (amino-N-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione (2) was dissolved in 5mL of anhydrous DMF, and pH was adjusted to 9 with N-methylmorpholine to give reaction solution B. Reaction B was added to reaction A and stirred at room temperature for 12 hours, and TLC (dichloromethane/methanol, 10/1) showed completion of the reaction. The reaction mixture was filtered, the filtrate was concentrated under reduced pressure, and the residue was purified by silica gel column chromatography (dichloromethane/methanol, 50/1) to give 0.35g (55%) of the title compound as a colorless solid. ESI-MS (M/z):633[ M + H]+1H NMR(300MHz,DMSO-d6)δ/ppm=10.940(s,1H),8.043(d,J=1.8Hz,1H),7.831(m,2H),7.709(t,J=5.4Hz,1H),7.567(d,J=7.8Hz,1H),7.332(m,6H),7.040(m,2H),6.940(td,J1=7.8Hz,J2=0.9Hz,1H),5.012(m,2H),4.069(m,1H),3.222(dd,J1=14.7Hz,J2=4.5Hz,1H),2.993(m,6H),2.003(t,J=7.2Hz,2H),1.430(m,6H),1.194(m,6H)。
EXAMPLE 17 preparation of (3R,6S) -3- (Cbz-Gly-amino-n-hexanoylamino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione (5b)
Using examplesMethod of 16 from 0.32g (1.0mmol) Cbz-Gly-amino-n-hexanoic acid (4b) and 0.31g (1.0mmol) (3R,6S) -3- (amino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione (2) gives 0.30g (49%) of the title compound as a colourless solid. ESI-MS (M/z):619[ M + H]+1H NMR(300MHz,DMSO-d6)δ/ppm=10.905(s,1H),8.038(s,1H),7.830(m,2H),7.685(s,1H),7.571(d,J=7.8Hz,1H),7.347(m,6H),7.045(m,2H),6.949(t,J=7.2Hz,1H),5.033(s,2H),4.074(m,1H),3.572(d,J=5.7Hz,2H),3.257(dd,J1=14.4Hz,J2=4.2Hz,1H),2.953(m,6H),2.008(t,J=7.2Hz,2H),1.434(m,6H),1.235(m,6H)。
EXAMPLE 18 preparation of (3R,6S) -3- (Cbz-Ile-amino-n-hexanoylamino) -6- (indole-3-methyl) -piperazine-2, 5-dione (5c)
From 0.38g (1.0mmol) Cbz-Ile-amino-n-hexanoic acid (4c) and 0.31g (1.0mmol) (3R,6S) -3- (amino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione (2) 0.12g (17%) of the title compound were obtained as colorless solid using the method of example 16. ESI-MS (M/z):675[ M + H]+1H NMR(300MHz,DMSO-d6)δ/ppm=10.902(s,1H),8.058(d,J=2.1Hz,1H),7.862(m,2H),7.695(t,J=5.4Hz,1H),7.563(d,J=7.8Hz,1H),7.299(m,6H),7.037(m,2H),6.941(td,J1=6.9Hz,J2=0.9Hz,1H),5.015(s,2H),4.065(m,1H),3.803(m,1H),3.252(dd,J1=14.4Hz,J2=4.2Hz,1H),2.979(m,6H),1.990(t,J=7.2Hz,2H),1.419(m,8H),1.175(m,7H),0.823(m,6H)。
EXAMPLE 19 preparation of (3R,6S) -3- (Cbz-Leu-amino-n-hexanoylamino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione (5d)
From 0.38g (1.0mmol) Cbz-Leu-aminon-hexanoic acid (4d) and 0.31g (1.0mmol) of (3R,6S) -3- (amino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione (2) by the method of example 16, 0.10g (15%) of the title compound are obtained as a colourless solid. ESI-MS (M/z):675[ M + H]+1H NMR(300MHz,DMSO-d6)δ/ppm=10.908(s,1H),8.055(s,1H),7.868(m,2H),7.691(t,J=5.4Hz,1H),7.561(d,J=7.8Hz,1H),7.325(m,6H),7.035(m,2H),6.940(t,J=7.2Hz,1H),5.010(m,2H),4.060(m,1H),3.962(m,1H),3.258(dd,J1=14.4Hz,J2=4.5Hz,1H),2.942(m,6H),1.994(t,J=7.2Hz,2H),1.471(m,8H),1.312(m,6H),0.850(m,6H)。
EXAMPLE 20 preparation of (3R,6S) -3- (Cbz-Val-amino-n-hexanoylamino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione (5e)
From 0.36g (1.0mmol) of Cbz-Val-amino-n-hexanoic acid (4e) and 0.31g (1.0mmol) of (3R,6S) -3- (amino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione (2) by the method of example 16, 0.12g (18%) of the title compound are obtained as a colorless solid. ESI-MS (M/z):661[ M + H]+1H NMR(300MHz,DMSO-d6)δ/ppm=10.927(s,1H),8.023(s,1H),7.925(s,1H),7.722(t,J=5.4Hz,1H),7.698(t,J=5.4Hz,1H),7.556(d,J=7.8Hz,1H),7,314(m,6H),7.036(m,2H),6.957(t,J=7.5Hz,1H),5.011(s,2H),4.065(m,1H),3.942(m,1H),3.248(dd,J1=14.6Hz,J2=4.2Hz,1H),2.964(m,6H),1.996(t,J=7.2Hz,2H),1.841(m,1H),1.439(m,6H),1.305(m,6H),0.851(d,J=6.6Hz,3H),0.792(d,J=6.6Hz,3H)。
EXAMPLE 21 preparation of (3R,6S) -3- (Ala-amino-n-hexanoylamino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione (6a)
From 0.06g (0.1mmol) of (3R,6S) -3- (Cbz-Ala-amino-n-hexanoylamino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione (5a) 0.05g (97%) of the title compound are obtained as colorless solid according to the method of example 4. ESI-MS (M/z):499[ M + H]+;Mp 145-146℃;
Figure GDA0002419745560000061
(c ═ 0.1, methanol); IR (cm)-1):3233,3083,2931,2862,1659,1556,1454,1325,1259,1102,1010,743;1H NMR(300MHz,DMSO-d6)δ/ppm=10.492(s,1H),8.400(t,J=5.4Hz,1H),8.052(d,J=1.8Hz,3H),7.854(s,1H),7.739(t,J=5.4Hz,1H),7.569(d,J=7.8Hz,1H),7.321(d,J=7.8Hz,1H),7.062(m,2H),6.969(td,J1=7.8Hz,J2=0.9Hz,1H),4.068(m,1H),3.754(m,1H),3.272(dd,J1=14.7Hz,J2=4.5Hz,1H),3.047(m,6H),2.018(t,J=7.2Hz,2H),1.438(m,6H),1.329(d,J=6.9Hz,3H),1.229(m,6H)。
EXAMPLE 22 preparation of (3R,6S) -3- (Gly-amino-n-hexanoylamino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione (6b)
From 0.06g (0.1mmol) of (3R,6S) -3- (Cbz-Gly-amino-n-hexanoylamino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione (5b) 0.05g (94%) of the title compound are obtained as colorless solid according to the method of example 4. ESI-MS (M/z):485[ M + H]+;Mp 115-117℃;
Figure GDA0002419745560000071
(c ═ 0.1, methanol); IR (cm)-1):3227,3065,2932,2855,1658,1545,1460,1322,1270,1189,1096,1015,922,744;1H NMR(300MHz,DMSO-d6)δ/ppm=10.925(s,1H),8.141(t,J=5.4Hz,1H),8.055(s,1H),7.719(t,J=5.4Hz,1H),7.571(d,J=7.8Hz,1H),7.323(d,J=7.8Hz,1H),7.045(m,2H),6.949(t,J=7.5Hz,1H),4.074(m,1H),3.345(s,2H),3.257(dd,J1=14.7Hz,J2=3.9Hz,1H),2.997(m,6H),2.016(t,J=6.9Hz,2H),1.438(m,6H),1.229(m,6H)。
EXAMPLE 23 preparation of (3R,6S) -3- (Ile-amino-n-hexanoylamino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione (6c)
From 0.07g (0.1mmol) of (3R,6S) -3- (Cbz-Ile-amino-n-hexanoylamino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione (5c) 0.05g (91%) of the title compound are obtained as colorless solid according to the method of example 4. ESI-MS (M/z):541[ M + H]+;Mp 96-98℃;
Figure GDA0002419745560000072
(c ═ 0.1, methanol); IR (cm)-1):3274,3094,2929,2863,1650,1537,1434,1324,1102,741;1H NMR(300MHz,DMSO-d6)δ/ppm=10.922(s,1H),8.040(d,J=2.1Hz,1H),7.848(s,1H),7.771(t,J=5.4Hz,1H),7.679(t,J=5.4Hz,1H),7.570(d,J=7.8Hz,1H),7.318(d,J=7.8Hz,1H),7.043(m,2H),6.947(td,J1=6.9Hz,J2=0.9Hz,1H),4.074(m,1H),3.255(dd,J1=14.4Hz,J2=4.2Hz,1H),2.974(m,7H),2.004(t,J=7.2Hz,2H),1.438(m,8H),1.229(m,7H),0.811(m,6H)。
EXAMPLE 24 preparation of (3R,6S) -3- (Leu-amino-n-hexanoylamino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione (6d)
From 0.07g (0.1mmol) of (3R,6S) -3- (Cbz-Leu-amino-n-hexanoylamino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione (5d) 0.05g (96%) of the title compound are obtained as colorless solid according to the method of example 4. ESI-MS (M/z):541[ M + H]+;Mp 164-165℃;
Figure GDA0002419745560000073
(c ═ 0.1, methanol); IR (cm)-1):3231,3077,2928,2863,1654,1549,1456,1322,1233,1096,1011,922,748;1H NMR(300MHz,DMSO-d6)δ/ppm=10.904(s,1H),8.055(s,1H),7.858(s,1H),7.803(t,J=5.4Hz,1H),7.694(t,J=5.4Hz,1H),7.569(d,J=7.8Hz,1H),7.318(d,J=7.8Hz,1H),7.043(m,2H),6.947(t,J=7.2Hz,1H),4.070(m,1H),3.255(dd,J1=14.4Hz,J2=4.5Hz,1H),2.992(m,7H),1.997(t,J=7.2Hz,2H),1.846(m,1H),1.438(m,7H),1.229(m,6H),0.855(d,J=6.6Hz,3H),0.780(d,J=6.6Hz,3H)。
EXAMPLE 25 preparation of (3R,6S) -3- (Val-amino-n-hexanoylamino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione (6e)
From 0.07g (0.1mmol) of (3R,6S) -3- (Cbz-Val-amino-n-hexanoylamino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione (5e) 0.05g (96%) of the title compound are obtained as colorless solid according to the method of example 4. ESI-MS (M/z):527[ M + H]+;Mp149-151℃;
Figure GDA0002419745560000081
(c ═ 0.1, methanol); IR (cm)-1):3223,3074,2936,2876,1658,1549,1435,1322,1253,1100,744;1H NMR(300MHz,DMSO-d6)δ/ppm=10.887(s,1H),8.050(s,1H),7.852(s,1H),7.792(t,J=5.4Hz,1H),7.689(t,J=5.4Hz,1H),7.563(d,J=7.8Hz,1H),7,312(d,J=7.8Hz,1H),7.038(m,2H),6.942(t,J=7.5Hz,1H),4.065(m,1H),3.250(dd,J1=14.6Hz,J2=4.2Hz,1H),2.964(m,7H),1.992(t,J=7.2Hz,2H),1.839(m,1H),1.432(m,6H),1.229(m,6H),0.849(d,J=6.6Hz,3H),0.773(d,J=6.6Hz,3H)。
EXAMPLE 26 preparation of Boc-amino-n-hexanoic acid
To a solution of 0.26g (2.0mmol) of aminon-hexanoic acid in 5mL of distilled water was added 0.58g (2.6mmol) (Boc) with stirring2Solution of O with 5mL dioxane. The resulting solution was adjusted to pH 9 with an aqueous solution of NaOH (2M) in ice bath. After stirring for 30 minutes in an ice bath, the mixture was stirred at room temperature and pumped down by a water pump. The pH was monitored during stirring and kept at 9 all the time until TLC (dichloromethane/methanol, 3/1) indicated completion of the reaction. The reaction mixture was saturated with KHSO under ice-bath4Adjusting pH of the aqueous solution to 7, and concentrating under reduced pressure. The aqueous phase is saturated KHSO4Adjusting pH to 2 with water solution, washing with 10mL ethyl acetate for three times, washing with 10mL saturated NaCl water solution for three times to make solution pH 7, and adding anhydrous Na2SO4Drying for 12 hours. Filtering to remove Na2SO4The filtrate was concentrated under reduced pressure to give 0.41g (89%) of the title compound as a colorless solid. ESI-MS (M/e):232[ M + H]+
EXAMPLE 27 preparation of (3R,6S) -3- (Boc-amino-n-hexanoylamino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione (7)
From 0.28g (1.2mmol) Boc-amino-n-hexanoic acid and 0.38g (1.2mmol) (3R,6S) -3- (amino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione (2) 0.12g (19%) of the title compound was obtained as a colorless solid using the method of example 16. ESI-MS (M/z):528[ M + H]+1H NMR(300MHz,DMSO-d6)δ/ppm=10.903(s,1H),8.046(d,J=1.8Hz,1H),7.851(s,1H),7.686(t,J=5.4Hz,1H),7.556(d,J=7.8Hz,1H),7.314(d,J=7.8Hz,1H),7.039(m,2H),6.943(td,J1=7.8Hz,J2=0.6Hz,1H),6.758(t,J=5.4Hz,1H),4.068(m,1H),3.252(dd,J1=14.4Hz,J2=4.2Hz,1H),2.924(m,6H),1.995(t,J=7.2Hz,2H),1.292(m,21H)。
EXAMPLE 28 preparation of (3R,6S) -3- (amino-n-hexanoylamino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione (8)
From 0.11g (0.2mmol) of (3R,6S) -3- (Boc-amino-n-hexanoylamino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione (7) by the method of example 2, 0.08g (96 g) were obtained%) the title compound as a colorless solid. ESI-MS (M/z):428[ M + H]+1H NMR(300MHz,DMSO-d6)δ/ppm=10.924(s,1H),8.071(s,1H),7.866(s,1H),7.729(t,J=5.4Hz,1H),7.568(d,J=7.5Hz,1H),7.321(d,J=7.5Hz,1H),7.044(m,2H),6.949(t,J=7.5Hz,1H),4.070(m,1H),3.239(dd,J1=14.4Hz,J2=3.6Hz,1H),2.991(m,4H),2.694(m,2H),2.021(t,J=7.5Hz,2H),1.467(m,6H),1.240(m,6H)。
EXAMPLE 29 determination of the anti-tumor metastasis Activity of Compounds 6a-e
The assay model was inoculated with Lewis mouse lung carcinoma cells (LLC, purchased from ATCC) in DMEM medium (containing 10% inactivated fetal bovine serum, 1X 10)5U/L penicillin and 100mg/L streptomycin), and the cells are enriched by passage every two days according to an adherent cell culture method. Digesting the cells when the cells are in good growth state and in logarithmic growth phase, and adjusting the cell density to 1 × 10 with physiological saline7one/mL. Staining with placental blue to count viable cells>95 percent. Inbred C57BL/6 male mice (SPF grade, body weight 20. + -.2 g) were taken and left-handed mice fixed. The right anterior limb axillary skin of the mouse was disinfected with 75% ethanol. The LLC tumor cell suspension is injected subcutaneously into the axilla of a mouse with a 1mL sterile syringe held in the right hand, and 0.2mL is injected into each mouse. After the mice are inoculated for 10 days, tumors with the diameter of about 4-5mm grow out, namely the tumor source. The Lewis lung cancer tumor-bearing mice are inoculated for 10 days and anesthetized by ether, and then the cervical vertebrae are removed for killing. Soaking in 75% ethanol for 10min, sterilizing, and removing tumor on clean bench. Well-grown tumor tissue was selected, minced in a sterile plate, and placed in a tissue homogenizer made of glass. Adding physiological saline with the temperature of 4 ℃ according to the ratio of the tumor mass to the volume of the physiological saline of 1 to 3(g to mL), and lightly grinding to prepare the cell suspension. The cell suspension is screened by 200-mesh cells to prepare single cell suspension. Adjusting the cell density of the single cell suspension to 1.5X 10 with physiological saline7one/mL. Staining with placental blue to count viable cells>95 percent. Left-handed inbred C57BL/6 male mice were fixed and their right anterior limb axillary skin was disinfected with 75% ethanol. The tumor cell suspension was injected subcutaneously into the mouse axilla with a 1mL sterile syringe in the right hand, 0.2mL each. 10 days after inoculation, mice developed tumors of 4-5mm in diameter, as measuredTumor volume inoculated mice were randomly grouped. Each group had 12 mice. Mice on day 11 of tumor inoculation were orally administered either a 20 μmol/kg/day normal saline solution of the putative anti-tumor metastasis peptide Arg-Gly-Asp-Ser (RGDS) or a 5 μmol/kg/day normal saline solution of Compound 8 or a 0.5 μmol/kg/day normal saline solution of Compounds 6a-e or a 10 mL/kg/day normal saline solution 1 time a day for 12 consecutive days. The next day of the last administration, cervical spine was removed by ether anesthesia, and the lungs of the mice were taken and the number of tumor nodules that metastasized in the tumor lungs was calculated. Statistical analysis of the data was performed using the t-test. The results are shown in Table 1. Compounds 6a-e were not only effective in inhibiting tumor lung metastasis at 0.5 μmol/kg dose, but also had no significant difference in activity from RGDS at 40-fold higher doses and compound 8 at 10-fold higher doses. These data indicate that the present invention has significant technical effects.
TABLE 1 antitumor metastatic Activity of Compounds 6a-e
Figure GDA0002419745560000091
a) P <0.01 to saline, p >0.05 to RGDS and compound 8; n is 12.
EXAMPLE 30 determination of the anti-inflammatory Activity of Compounds 6a-e
Since xylene-induced ear swelling in mice is recognized as an acute inflammation model, the present invention measures the therapeutic effect of compounds 6a-e on a xylene-induced ear swelling model in mice. Because aspirin is a positive drug for treating acute inflammation, aspirin is selected as a positive control in the present invention. ICR male mice (SPF grade, body weight 20 ± 2g) were allowed to rest for 2 days at 22 ℃ with free access to water and food. Thereafter, the mice were randomly divided into a saline group (dose: 0.2 mL/mouse), an aspirin group (dose: 1110. mu. mol/kg), a Compound 8 group (dose: 5. mu. mol/kg) and Compound 6a-e groups (dose: 0.5. mu. mol/kg), and 12 mice were each group. Mice were tested either orally in normal saline, orally in aspirin, or orally in compound 6a-e, as indicated by group. After 30min of administration, the left auricle of the mouse was evenly smeared with 30 μ L of xylene, and after 2h, the mouse was subjected to ether anesthesia, the neck was cut off, the left and right ears were cut off, round ears were taken at the same positions of the two ears by a 7mm punch, and the difference in swelling between the two ears was weighed and found to be the swelling degree. Namely the swelling degree is equal to the weight of the left ear disk to the weight of the right ear disk. The results are shown in Table 2. Not only can the compounds 6a-e effectively inhibit mouse ear swelling caused by xylene at a dose of 0.5. mu. mol/kg, but also the activity is not significantly different from that of aspirin which is 2220 times higher than the dose and compound 8 which is 10 times higher than the dose. These data indicate that the present invention has significant technical effects.
TABLE 2 Effect of Compounds 6a-e on xylene-induced ear swelling in mice
Figure GDA0002419745560000101
a) P <0.01 to saline, p >0.05 to aspirin and compound 8; n is 12.

Claims (4)

1. (3R,6S) -3- (AA-amino-n-hexanoylamino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione of the formula,
Figure FDA0002419745550000011
wherein AA is L-Ala residue, Gly residue, L-IIe residue, L-Leu residue and L-Val residue.
2. A process for the preparation of (3R,6S) -3- (AA-amino-n-hexanoylamino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione according to claim 1, which comprises:
(1) D-Boc-Lys (Cbz) and L-Trp-OBzl are condensed to obtain D-Boc-Lys (Cbz) -L-Trp-OBzl;
(2) removing Boc from D-Boc-Lys (Cbz) -L-Trp-OBzl in ethyl acetate solution of hydrogen chloride to obtain D-Lys (Cbz) -L-Trp-OBzl;
(3) the ethyl acetate solution of D-Lys (Cbz) -L-Trp-OBzl is fully washed by saturated sodium bicarbonate aqueous solution, and then cyclization is carried out to obtain (3R,6S) -3- (benzyloxycarbonylamino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione (1);
(4) the compound 1 is subjected to hydrogenolysis to remove benzyloxycarbonyl to obtain (3R,6S) -3- (amino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-diketone (2);
(5) condensing amino methyl hexanoate and Cbz-AA to obtain Cbz-AA-amino methyl hexanoate (3a-e), wherein AA is an L-Ala residue, a Gly residue, an L-IIe residue, an L-Leu residue and an L-Val residue;
(6) saponifying and removing methyl ester from the compound 3a-e to obtain Cbz-AA-amino n-hexanoic acid (4 a-e);
(7) condensing the compound 2 and a compound 4a-e to obtain (3R,6S) -3- (Cbz-AA-amino n-hexanoylamino n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-diketone (5 a-e);
(8) the compound 5a-e is subjected to hydrogenolysis to remove the benzyloxycarbonyl to obtain (3R,6S) -3- (AA-amino-n-hexanoylamino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione (6 a-e).
3. Use of (3R,6S) -3- (AA-amino-n-hexanoylamino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione according to claim 1 for the preparation of a medicament against tumor metastases.
4. Use of (3R,6S) -3- (AA-amino-n-hexanoylamino-n-butyl) -6- (indole-3-methyl) -piperazine-2, 5-dione according to claim 1 for the preparation of an anti-inflammatory medicament.
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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61112060A (en) * 1984-11-02 1986-05-30 Fujisawa Pharmaceut Co Ltd Piperazine compound
CN105272980A (en) * 2014-06-10 2016-01-27 首都医科大学 (3R,12aS)-3-(4-aminobutyl)-2,3,6,7,12,12a-hexahydropyrazino[1',2':1,6]pyrido[3,4-b]indole-1,4-dione, and preparation and application thereof
CN105503833A (en) * 2014-10-20 2016-04-20 首都医科大学 Indole piperazine dione compound, and preparation and treatment effect thereof

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61112060A (en) * 1984-11-02 1986-05-30 Fujisawa Pharmaceut Co Ltd Piperazine compound
CN105272980A (en) * 2014-06-10 2016-01-27 首都医科大学 (3R,12aS)-3-(4-aminobutyl)-2,3,6,7,12,12a-hexahydropyrazino[1',2':1,6]pyrido[3,4-b]indole-1,4-dione, and preparation and application thereof
CN105503833A (en) * 2014-10-20 2016-04-20 首都医科大学 Indole piperazine dione compound, and preparation and treatment effect thereof

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