Olefination of dialkyl squarates 1–5 with several ylides 6 and phosphonates 7 gave the corresponding alkylidene products 8–12. In the case of Horner-Emmonsreactions, stereoselective formation of Z-alkylidene products was observed. An acid-catalyzed hydrolysis of 8–12 gave squarylacetic acid esters 13.
[EN] 2-ALKOXY-CYCLOBUTENE-3,4-DIONE DERIVATIVES, PREPARATION AND THERAPEUTIC USE THEREOF<br/>[FR] DERIVES DE 2-ALCOXY-CYCLOBUTANE-3,4-DIONE LEUR PREPARATION ET LEUR APPLICATION EN THERAPEUTIQUE
申请人:SANOFI SYNTHELABO
公开号:WO2000063160A1
公开(公告)日:2000-10-26
Les composés répondent à la formule générale (I) dans laquelle: R1 and R2 représentant, indépendamment l'un de l'autre, un atome d'hydrogène ou un groupe C1-3 alkyle, R3 représente un atome d'hydrogène ou un groupe C1-6 alkyle, W représente un groupe OR4, et R4 représente un groupe C1-10 alkyle, C2-6 alkényle, C2-6 alkynyle, C3-6 cycloalkyle-C1-3 alkyle-, benzyle, ou C1-6 fluoroalkyle. Application thérapeutique.
Dicyclopentyl Dithiosquarate as an Intermediate for the Synthesis of Thiosquaramides
作者:Michael Rombola、Viresh H. Rawal
DOI:10.1021/acs.orglett.7b03549
日期:2018.2.2
for the synthesis of a variety of thiosquaramides from a common dithionated intermediate. Both diaryl thiosquaramides and bifunctional thiosquaramides are readily accessed from dicyclopentyl dithiosquarate via two addition–elimination reactions. The convenient handling characteristics and relative stability of associated intermediates enable an operationally simple thiosquaramide preparation. Bifunctional