N-(3-巯基丙酰基)-N-芳基甘氨酸(14a-x),-N-芳基丙氨酸(15a,b),-N-环烷基甘氨酸(16a-k)和-1,2,3,4-的合成描述了四氢异喹啉-3-羧酸(17a-d),-1,2,3,4-四氢喹啉-2-羧酸(18a-f)和-二氢吲哚-2-羧酸(19a-k)。报道了每种化合物对血管紧张素转化酶(ACE)的体外抑制作用,并讨论了每个系列的结构-活性关系。讨论了ACE的体内抑制作用和各系列代表性化合物的降压作用。最有效的化合物19d的体外ACE IC50为2.6 X 10(-9)M,并且以10 mg / kg po的剂量在85 mm的自发性高血压大鼠中降低了血压。
Organocatalytic enantioselective transient enolate protonation in conjugate addition of thioacetic acid to α-substituted N-acryloyloxazolidinones
作者:Rajshekhar A. Unhale、Nirmal K. Rana、Vinod K. Singh
DOI:10.1016/j.tetlet.2013.01.004
日期:2013.4
Organocatalytic conjugate addition of thioacetic acid to a series of α-substituted N-acryloyloxazolidin-2-ones followed by enantioselectiveprotonation has been studied in the presence of thiourea catalysts derived from cinchona alkaloids. Conjugate addition/protonation adducts have been obtained up to 97% ee and high yields. The methodology could serve as an easy and practical route to the syntheses
A synthesis of N-(3-mercapto-2-D-methylpropanoyl)-L-proline (1, Captopril) is described in which the key intermediate, optically active 3-chloro-2-D-methylpropanoyl chloride (3b), was prepared by treating microbiologically derived optically active 3-hydroxy-2-D-methylpropanoic acid (2) with thionyl chloride. The compound 3b was coupled with L-proline to afford the chloride (4) which was directly converted into Captopril by reaction with hydrosulfide or trithiocarbonate ion in hot water with retention of the stereochemistry. The preparation of another useful intermediate, 3-acetylthio-2-D-methylpropanoic acid (9a), is also described.
A cyclic iminocarboxylic acid derivative of the formula: ##STR1## or a salt thereof, wherein X.sup.1 and X.sup.2 are each hydrogen, halogen, lower alkoxy, lower alkyl, trifluoromethyl, nitro, amino, alkylamino, aralkylamino, acetylamino or ethoxycarbonylamino, Y is --CO-- or --SO.sub.2 --, Z is --CH.sub.2 -- or --S--, and R is hydrogen or lower alkyl. Such compounds are useful as antihypertensive agents.
A set of novel apomorphine derivatives were synthesized with diversely functionalized side chains in the proximity of position 2 of the aporphine skeleton. Amino and/or carboxylic functions were introduced to this region of the backbone to test their pharmacological effects. During the synthesis of 2-(S-3-mercaptopropionic acid)-derivative a heteroring-fused congener was also isolated. The structural elucidation confirmed that the formation of this product was in accordance with our previous observations on the reaction of thebaine (2) with thiosalycilic acid. All the novel apomorphine congeners 4a-g were neuropharmacologically characterized to discover their dopaminergic profiles. Two derivatives were identified as D-2 full agonists equipotent with apomorphine (1) having significantly increased D-2/D-1 selectivity ratios. (C) 2011 Elsevier Masson SAS. All rights reserved.