A series of novel compounds having a benzothiazoline skeleton was studied for their structure-activity relationship (SAR) with respect to Ca2+ antagonistic activity. As test compounds, analogues of 3-acyl-2-arylbenzothiazolines (3) were synthesized. Benzothiazoline derivatives (3) exerted higher Ca2+ antagonistic activity than the corresponding thiazolidine derivatives (2). Effects of substituents
Nickel-catalyzed reductive coupling of arylcarboxylic acid 2-pyridyl esters with alkyl methanesulfonates: access to alkyl aryl ketones
作者:Hang Yu、Zhong-Xia Wang
DOI:10.1039/d3ob00293d
日期:——
Alkyl aryl ketones were synthesized via a nickel-catalyzed reductive coupling reaction of arylcarboxylic acid (2-pyridyl)esters with primary and secondary alkylmethanesulfonates under mild reaction conditions. This method suits a wide range of substrates and shows good compatibility with functional groups.
This invention relates to benzothiazine derivatives represented by the formula [I] and salts thereof, which are useful for treatment of cardiovascular diseases.
本发明涉及由式[I]代表的苯并噻嗪衍生物及其盐类,可用于治疗心血管疾病。
Novel convenient synthesis of biologically active esters of hydroxylamine
作者:Maxim A. Khomutov、Swati Mandal、Janne Weisell、Neiha Saxena、Alina R. Simonian、Jouko Vepsalainen、Rentala Madhubala、Sergey N. Kochetkov
DOI:10.1007/s00726-009-0410-0
日期:2010.2
Alkylation of ethyl N-hydroxyacetimidate with readily available methanesulfonates of functionally substituted alcohols and subsequent deprotection of aminooxy group is a novel and convenient method to prepare functionally substituted esters of hydroxylamine with high overall yield. This approach is a good alternative to well-known reaction of N-hydroxyphthalimide with alcohols under the Mitsunobu conditions. The properties of ethoxyethylidene protection of aminooxy group on the contrary to that of N-alkoxyphthalimide group allow to perform a wide spectra of the transformations in the radical of N-protected hydroxylamine derivatives. This is essential for synthetic strategies consisting in the introduction of N-protected aminooxy group at one of the first steps of synthesis and subsequent transformations of the radical.The inhibitory effect of one of the newly synthesized compound, 1-guanidinooxy-3-aminopropane (GAPA), was compared with that of well-known inhibitors of ornithine decarboxylase namely, alpha-difluoromethylornithine (DFMO) and 1-aminooxy-3-aminopropane (APA) on Leishmania donovani, a protozoan parasite that causes visceral leishmaniasis. GAPA, on the contrary with APA and DFMO, in micromolar concentrations, inhibited the growth of both amastigotes and promastigotes of sodium antimony gluconate-resistant forms of L. donovani.
YAMAMOTO, KOJI;FUJITA, MASANOBU;TABASHI, KEIZO;KAWASHIMA, YOICHI;KATO, EI+, J. MED. CHEM., 31,(1988) N 5, 919-935