CN1217924C - Fluoro labelled aliphatic acid myocardial metabolic imaging agent 14 (R,S)-Fluoro[18F]-6-thio cydonic acid purifying method - Google Patents

Abstract

The present invention relates to a method for purifying a fluoro labelled aliphatic acid myocardial metabolic imaging agent 14 (R S)-Fluoro(18<F>)-6-thio heptadecanoic acid, particularly to synthesis of radioactive positron medicine. In the reference literature of the present invention, 8-bromine-1-octanol as raw materials is synthesized step by step to obtain labelled precursor 14(R, S)-(p-toluenesulfonyl)-6-thio-heptadecanoic acid benzyl ester FTHA-OTs and nonradioactive FTHA, and the nucleophilic fluorin labeling of the labelled precursor is carried out to prepare (18)<F>-FTHA. The present invention improves the synthetic method in the literature and purification method for products after nucleophilic fluorin labeling, reaction mixture is prepared without HPLC separation, but by adding in distilled water while hot after the ester hydrolyzes, or by Sep-Pak18C column separation. The present invention has the advantages of simple operation and little time consumption, and the radiological chemistry yield and purity of (18)<F>-FTHA are enhanced. The retention time of FTHA and (18)<F>-FTHA is consistent through detection.

Description

A kind of fluorine mark lipid acid myocardial metabolic agent 14 (R, S)-fluorine [ 18F]-purification process of 6-sulphur margaric acid

Technical field

A kind of fatty acid metabolism developer 14 (R, S)-fluorine [ ¹⁸F]-purification process of 6-sulphur margaric acid, relate to a kind of fluorine mark lipid acid myocardial metabolic agent.

Background technology

Over past ten years, positron emission fault (PET) video picture has been widely used in the clinical and fundamental research of tumour, neuropsychiatric disease and cardiovascular disorder etc. clinically, and progressively becomes the new scientific research method of gene function and new drug development research.The application of PET and development be unable to do without the PET positron emitting tracer, and clinical positron emitting tracer commonly used because the transformation period is short, can not rely on from external import, lean on development voluntarily.In medical short-half-life nucleic, ¹⁸F has the relatively long transformation period (110min), can closely use in addition at the PET center, and is in recent years, right abroad ¹⁸The research Showed Very Brisk of the various positron emitting tracers of F mark.

The problem of myocardial viability estimation is the focus of nuclear cardiology in recent years always, though ²⁰¹Tl and ^99mTc-MIBI single photon computerized tomography (SPECT) myocardial perfusion imaging has been done highly effective work, but the PET aspect, glucose ( ¹⁸F-FDG) myocardial metabolic imaging and ¹³NH ₃Myocardial perfusion imaging is acknowledged as " gold " standard of judging myocardial viability.Abroad, the work of lipid acid cardiac muscle SPECT metabolism video picture is very deep, domestic owing to not can manufacture ¹²³I, this work can't be goed deep into.

Lipid acid is the main energy derive of cardiac muscle, and myocardium fatty acid metabolism and myocardium residing state are closely related, and when myocardial ischaemia, the picked-up of myocardium lipid acid and removing also change thereupon, so fluorine mark lipid acid can be used for the estimation of myocardial cell's survival.Relatively more successful in recent years has ¹⁸F-FTHA and ¹⁸F-FTP respectively at 6 and 4 assorted unisulfur stoms of longer chain fatty acid, has reduced the beta-oxidation speed of lipid acid, obviously prolongs its residence time in cardiac muscle, studies show that ¹⁸F mark lipid acid is by plastosome oxidation picked-up, and the myocardium radioactivity speed of concentrating can reflect the rate of oxidation of longer chain fatty acid, has been used for clinical atraumatic ground at present and has measured myocardium substrate utilization state, instructs clinical drug therapy.

Summary of the invention

The purpose of this invention is to provide a kind of fatty acid metabolism developer 14 (R, S)-fluorine [ ¹⁸F]-purification process of 6-sulphur margaric acid, the synthetic method of document is improved.

Technical scheme of the present invention

The synthetic method of FTHA

Reference literature of the present invention (Degrado TR, et al, J.Labelled Comps andRadiopharmaceuticals, Vol.X X IX, No.9; 989-995) (R S)-p-toluenesulfonyl-6-sulphur-heptadecane acid benzyl ester (FTHA-OTs), carries out the nucleophilic displacement labeled reactant to preparation labelled precursor 14 again, obtains ¹⁸The F marked product ¹⁸F-FTHA.The invention reside in the fluorine marked product ¹⁸The purification process of F-FTHA, the method of above-mentioned document is that reaction mixture is separated preparation with HPLC, obtain product, and the present invention is improved to after mark finishes, employing 1) adds acetate (50 μ l) and water (1ml) immediately after the ester hydrolysis, the solution that anhydrates that inclines, with ethanol (0.5～1ml), will be adsorbed on the reaction tube wall ¹⁸F-FTHA washes, and in the clean bottle of solution transfer to, obtains product, or 2) add KOH solution, behind 90～95 ℃ of ester hydrolysis 5min, put coldly, add acetate (50 μ l), water (1ml), reaction mixture are used ethanol activatory Sep-Pak after in advance ¹⁸The C post is used water for injection (10ml) flushing again, discards washing fluid, and (2.5ml) will be adsorbed on Sep-Pak with ethanol ¹⁸On the C post ¹⁸F-FTHA is dissolved in the clean bottle, crosses the aseptic filter membrane of 0.22 μ m, need not to separate preparation with HPLC.

Agents useful for same is to be 3～10mg in labelled precursor FTHA-OTs, and the ester hydrolyzate dissolves required reagent acetate 50 μ l, water 1ml, ethanol 0.5～1ml; Sep-Pak ¹⁸The C post flushing water 10ml of institute, ethanol 2.5ml.

Beneficial effect of the present invention

After the nucleophilic mark finished, reaction mixture separated preparation without HPLC, but 1) add entry while hot after the ester hydrolysis and carry out aftertreatment, 2) Sep-Pak used ¹⁸The C post separates preparation, compares with document, and the post-treating method that the present invention adopts is not only simple to operate, weak point consuming time, ¹⁸Radiochemical yield and the degree of F-FTHA also increase, and through ultraviolet and radioassay, ¹⁸The retention time of F-FTHA and FTHA is consistent.

Description of drawings

Fig. 1 ¹⁸F-FTHA and FTHA color atlas

Embodiment

1, ¹⁸The F mark

By ¹⁸O (p, n) ¹⁸The carrier free that the F reaction generates ¹⁸F ^-(740～1850MBq), be enriched on the anion-exchange column QMA, use 1ml K ₂CO ₃-K _2.2.2Solution to reaction tubes, dries up its drip washing under nitrogen gas stream in 105 ℃ of oil bath heating, resistates continues with anhydrous acetonitrile (3 * 1ml) azeotropic evaporates to dryness.Adding 14 (R, S)-(3～10mg) acetonitrile solution (1ml) reacts 20min in 90～95 ℃ of oil baths to tosyl group-6-sulphur-heptadecane acid benzyl ester.(0.2mol/L 0.5ml), continues to carry out ester hydrolysis reaction in 90～95 ℃ of oil baths to add potassium hydroxide in above-mentioned reaction tubes, behind the reaction 5min, a) add acetate (50 μ l) and water (1ml) immediately, the solution that anhydrates that inclines, (0.5～1ml) will be adsorbed on the reaction tube wall with ethanol ¹⁸In the penicillin bottle of F-FTHA solution transfer to a cleaning; B) reaction mixture is crossed Sep-Pak ¹⁸C post (activating with ethanol in advance), water (10ml) flushing again discards washing fluid, and (2.5ml) will be adsorbed on Sep-Pak with ethanol ¹⁸On the C post ¹⁸F-FTHA is dissolved in the penicillin bottle of a cleaning, crosses the aseptic filter membrane of 0.22 μ m.

2, ¹⁸The preparation of F-FTHA injection liquid

Before the injection, above-mentioned sample added in 4～6% HSA (or BSA) solution, in 37 ℃ hatch 30min after, cross the aseptic filter membrane of 0.22 μ m promptly.

3, RCP measures

TLC: with product ¹⁸The F-FTHA point sample is the developping agent ascending development in silica gel paper one end with the ether, dries the back areal survey, calculates RCP. ¹⁸The R of F-FTHA _fBe 0.9～1.0, free ¹⁸F ^-R _fValue is 0.0.

(3.9 * 150mm), moving phase is 85% acetonitrile to the HPLC:C-18 reversed-phase column, flow velocity 1.0ml/min.Get product ¹⁸F-FTHA 10 μ l (counting about 10K) sample introduction is used radioactive detector and UV-detector (λ=210nm) measure respectively ¹⁸F-FTHA and FTHA, whether the retention time of observing non-marked FTHA is consistent with the retention time at the radiation peak of marker, ¹⁸The Rt of F-FTHA is 8.78min, and is free ¹⁸F ^-The Rt value be 3.42min, the Rt of FTHA is-8.00min.

4, ¹⁸The F-FTHA study on the stability

The gained injection liquid is placed down in room temperature (25 ℃),, measured the RCP of marker respectively at 1h, 2h and 3h.

5, the mensuration of PC

Get marker (RCP＞90%, 5 * 10 ⁴Cpm) add respectively in n-Octanol-phosphate buffered saline buffer (0.1mo/LpH7.00 and 7.40) two-phase system (V/V=3/3), mixing, behind vortex vibration 3 * 1min, 4000 rev/mins of centrifugation 5min, in two pipes, get the 1ml n-Octanol and the 1ml aqueous solution respectively and survey counting, get the 1ml n-Octanol again and inject 3.0ml phosphate buffered saline buffer/2.0ml n-Octanol two-phase system, so repeat repeatedly, calculate [cpm _{Organic phase}/ cpm _Water] ratio, until constant, PC=lg[cpm _{Organic phase}/ cpm _Water]

6, ¹⁸The external plasma proteins combination of F-FTHA

Will ¹⁸F-FTHA (does not add BSA, radiocounting 5 * 10 ⁴Cpm), add to 1ml human serum albumin (HSA, 10g/L, pH7.40, PBS) in, hatch 15s, 30s, 1min, 3min, 5min, 10min, 30min, 1h, 1.5h and 2h respectively at 37 ℃ after, add 10% Tricholroacetic Acid 1ml, centrifugal 20min (4000 commentaries on classics/min) calculates ¹⁸The external protein binding rate of F-FTHA.

7, ¹⁸Distribute in the F-FTHA mouse body

Kunming mice, body weight 20～22g, 3 every group, totally 6 groups.The tail vein injects ¹⁸Behind the F-FTHA solution 0.2ml (about 3.7MBq), the different time sacrificed by decapitation, get internal organs such as blood, the heart, liver, spleen, lung, kidney and bone, weigh, simultaneously by injected dose preparation standard pipe, tracking measurement, the radioactivity of calculating each main organs account for the percent value of total injected dose (%ID/g wet tissue).

8, the rat serum medicine is removed kinetics

4 of SD rats are injected from femoral vein ¹⁸F-FTHA injection liquid 0.2ml (14.8MBq), 1min, 3min, 5min, 8min, 10min, 15min, 20min, 30min, 45min, 60min, 90min, 120min and 180min after injection, get blood 20 μ l from rat tail vein, survey radioactivity with gamma counter, simultaneously by injected dose preparation standard pipe, tracking measurement calculates and is converted into %ID/ml blood, makes radioactive activity---time curve.

9, undue toxicity experiment

3 of kunming mices (18-20g), the tail vein injects ¹⁸F-FTHA injection liquid 0.2ml (people's consumption 1/5), the conventional raising 48 hours, and the maximum accepted of the amount of accepting by the per kilogram mouse and per kilogram people than computationally secure multiple.

Claims (2)

1. A fluorine mark lipid acid myocardial metabolic agent 14 (R, S)-fluorine [ ¹⁸F]-purification process of 6-sulphur margaric acid, it is characterized in that, final marker 14 (R, S)-fluorine [ ¹⁸F]-purifying of 6-sulphur-margaric acid improves, adopts: add KOH solution, at 90～95 ℃ of 14 (R; S)-p-toluenesulfonyl-6-sulphur-heptadecane acid benzyl ester hydrolysis 5min after, put coldly, add acetate; water, reaction mixture are used ethanol activatory Sep-Pak after in advance ¹⁸The C post with the water for injection flushing, discards washing fluid again, will be adsorbed on Sep-Pak with ethanol ¹⁸On the C post 14 (R, S)-fluorine [ ¹⁸F]-6-sulphur-margaric acid is dissolved in the clean bottle, crosses the aseptic filter membrane of 0.22 μ m.
2. 2, purification process according to claim 1, it is characterized in that with labelled precursor 14 (R, S)-p-toluenesulfonyl-6-sulphur-heptadecane acid benzyl ester is 3～10mg meter, the ester hydrolyzate dissolves required reagent acetate 50 μ l, water 1ml, ethanol 0.5～1ml; Sep-Pak ¹⁸The C post flushing water 10ml of institute, ethanol 2.5ml.

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