New aspects of the formation of 2-substituted thiazolidine-4-carboxylic acids and their thiohydantoin derivatives
作者:Ahmed R. E. Mahdy、Elghareeb E. Elboray、Ragab F. Fandy、Hussien H. Abbas-Temirek、Moustafa F. Aly
DOI:10.24820/ark.5550190.p009.861
日期:——
readily with (R)-cysteine in boiling acidified methanol to give diastereomeric mixtures of the corresponding 2-(aryl substituted) thiazolidine-4-carboxylic acids. 4-Nitrobenzaldehyde under similar conditions afforded one isomer of 2-(4-nitrophenyl)thiazolidine-4-carboxylic acid, which epimerized in the NMR solvents into a diastereomeric mixture. 2-Nitrobenzaldehyde reacted with (R)-cysteine to afford 3
芳香醛很容易与 (R)-半胱氨酸在沸腾的酸化甲醇中反应,得到相应的 2-(芳基取代的)噻唑烷-4-羧酸的非对映异构体混合物。4-硝基苯甲醛在类似条件下得到 2-(4-硝基苯基)噻唑烷-4-羧酸的一种异构体,其在 NMR 溶剂中差向异构化为非对映异构混合物。2-硝基苯甲醛与 (R)-半胱氨酸反应得到 3,5-双-(2-硝基苯基)四氢-1H-噻唑并[3,4-c]恶唑-1-one 作为唯一产物,其在 NMR 中坍塌溶剂转化为噻唑烷-4-羧酸的非对映异构混合物。噻唑烷衍生物与异硫氰酸苯酯顺利反应,得到相应硫代乙内酰脲的单一异构体。