Earthworm Is a Versatile and Sustainable Biocatalyst for Organic Synthesis

Abstract

A crude extract of earthworms was used as an eco-friendly, environmentally benign, and easily accessible biocatalyst for various organic synthesis including the asymmetric direct aldol and Mannich reactions, Henry and Biginelli reactions, direct three-component aza-Diels-Alder reactions for the synthesis of isoquinuclidines, and domino reactions for the synthesis of coumarins. Most of these reactions have never before seen in nature, and moderate to good enantioselectivities in aldol and Mannich reactions were obtained with this earthworm catalyst. The products can be obtained in preparatively useful yields, and the procedure does not require any additional cofactors or special equipment. This work provides an example of a practical way to use sustainable catalysts from nature.

Synthesis of Anticogulant Warfarin and Its Derivatives by the Crude Earthwarm Extract

“…我们采用之前报道的方法来制备蚯蚓粗提物 [14] , 用新鲜的赤子爱胜蚓(Eisenia foetida)和去离子水制成匀 浆, 通过蔗糖透析浓缩, 再离心获得上清液, 干燥后研 /% 1 10 17 2 2 20 27 6 3 30 37 12 4 40 56 14 5 50 68 22 6 60 75 20 7 70 80 19 8 80 85 19 9 90 86 20 10 100 87 20 11 110 87 19 12 120 75 19 13 140 72 19…”

“…核磁共振波谱分析仪 Bruker-AM 600(600 MHz); 显微熔点仪 WPX-4(上海易测仪器设备有限公司). 蚯蚓 粗提物, 由我们课题组制备 [14] . 取代苄叉丙酮 2b, 2c, 2e, 2f, 2h, 2i, 2k 制备方法参见文献 [22].…”

Earthworms as a Biocatalyst: In Asymmetric Aldol Reactions

“…Our group recently reported that crude extract of earthworms, as a versatile, environmentally friendly, and sustainable biocatalyst, could catalyze various organic reactions including Mannich, aldol, Biginelli, Henry, aza-Diels-Alder reactions, and domino reactions for the synthesis of coumarin derivatives. 9,10 The asymmetric direct aldol reaction as one of the most powerful carbon-carbon bond formation methods has become one of the central study issues in organic synthesis. 11 In recent years, a lot of successful metal catalysts and organocatalysts for direct asymmetric aldol reactions have been reported with high efficiency and enantioselectivity, 12 including some methods under solvent-free mechanochemical conditions, [13][14][15] yet the development of eco-friendly and sustainable catalysts for the asymmetric aldol reaction is still a significant challenge.…”

“…22 Thus, we think it is still necessary to further explore the application of earthworm extract for the asymmetric direct aldol reaction and especially for the large-scale reaction, although we have concisely reported the use of earthworm extract in asymmetric direct aldol reaction in which eight examples were investigated. 9 Herein, we report detailed studies of earthworm extract-catalyzed asymmetric direct aldol reaction with largely expanded substrates, in which 18 new examples were included and a scale-up reaction was tested. This study further demonstrates the excellent utility of earthworm extract for asymmetric direct aldol reaction.…”

“…Our group recently reported that crude extract of earthworms, as a versatile, environmentally friendly, and sustainable biocatalyst, could catalyze various organic reactions including Mannich, aldol, Biginelli, Henry, aza-Diels-Alder reactions, and domino reactions for the synthesis of coumarin derivatives. 9,10…”