An imidazolide (4) obtained from carbobenzoxy-NG=-nitro-L-arginine (3) was reduced with lithium aluminum hydride to give carbobenzoxy-NG=-nitro- L-argininal (5) in good yield. The aldehyde (5) was converted into NG=-nitro-Largininal semicarbazone (7) which was coupled with an active ester of various acylated leucines or isoleucines and then deblocked, giving leupeptins and their analogs, as listed in Table 1. Antiplasmin activities of these compounds are discussed.
用
氢化铝锂还原从羧基苯氧基-NG=-硝基-
L-精氨酸(3)中得到的
咪唑内酯(4),得到羧基苯氧基-NG=-硝基-L-精
氨醛(5),收率很高。醛(5)被转化为 NG=-硝基-L-精
氨醛缩
氨基
脲(7),后者与各种酰化亮
氨酸或
异亮氨酸的活性酯偶联,然后脱锁,得到表 1 所列的亮肽及其类似物。对这些化合物的
抗蛋白酶活性进行了讨论。