Stereodivergent synthesis of both (2S)- and (2R)-1-monoricinolein derivatives by lipase-catalyzed hydrolysis or transesterification directed to new ferroelectric liquid crystals
摘要:
The preparation of both (2S)- and (2R)-1-monoricinolein derivatives has been developed to synthesize ferroelectric liquid crystals. Lipase-catalyzed hydrolysis of 2-protected-1,3-diricinoleins provided (2S)-1-monoricinolein derivatives with high diastereoselectivities, while transesterification of 2-protected glycerols with vinyl recinoleate gave (2R)-1-monoricinolein counterparts in good yields with high diastereoselectivities. (c) 2007 Elsevier Ltd. All rights reserved.
Enzymatic esterification of glycerol III. Lipase‐catalyzed synthesis of regioisomerically pure 1,3‐sn‐diacylglycerols and 1 (3)‐rac‐monoacylglycerols derived from unsaturated fatty acids
摘要:
摘要 利用具有高区域选择性和广泛底物耐受性的脂肪酶作为催化剂,在不可逆酰基转移条件下对甘油进行高效酯化。油酸、亚油酸、芥酸、蓖麻酸、羟基硬脂酸和科里奥利酸等多种不饱和脂肪酸以乙烯基酯的形式被用于此目的。在对生物催化剂的区域选择性(RE)和底物耐受性进行系统筛选的基础上,选择了合适的生物催化剂。实验发现,这些生物催化剂在特异性、选择性和非特异性方面存在明显差异,并以 RE 数值表示。在这些实验的基础上,以制备规模(150 毫摩尔)合成了多种分子,产率高(约 85%),区域异构纯度高(95% RE)。