Chemistry of Succinimido Esters. IV.

Abstract

A facile preparation of N-succinimidyl carboxylates (N-succinimidyl esters of fatty, substituted benzoic and aliphatic dicarboxylic acids) using N,N'-disuccinimidyl carbonate (DSC) was developed. The reactions of the acids with DSC in the presence of pyridine in acetonitrile gave the correspond ing esters in good yield. N-Hydroxysuccinimide formed during a reaction and pyridine could be easily removed by treatment with water. No by-products, of course, could be detected by HPLC and TLC analyses. The present method has advantages of high yields and purities of the desired esters, and of convinience for preparation of the N-succinimidyl esters, compared with the method using N, N'-dicyclohexylcarbodiimide t DCC). The structures of the resulting esters were determinded by mass spectrometry.

Chemistry of Succinimido Esters. IX.

“…2. 4 LG reaction in biphasic system A mixture of buffer solution (pH 6. 8, 0.05 M) containing LG solution (0.5 mg/mL, 2 mL) and hexane solution (25 mL) containing linoleic acid (2.5 mg/mL) was stirred at over 500 rpm at 30°C.…”

Synthesis of CID-cleavable protein crosslinking agents containing quaternary amines for structural mass spectrometry

“…Subsequent acid hydrolysis with concentrated HCl in acetic acid proceeded slowly, but cleanly, at 100 °C to provide diacid 5a as a mixed chloride/iodide salt. Activation of this to the bis-NHS ester was accomplished by mild heating of 5a with excess N , N ′-disuccinimidyl carbonate and pyridine in acetonitrile following a literature procedure 44 , whereas reaction in neat pyridine left only starting material. Unreacted starting diacid 5a was filtered away from 1a , which was then precipitated by slow addition of crude product, dissolved in minimal acetonitrile, into a large excess of cold ethyl acetate.…”