Nostosin A was the most potent natural tripeptide aldehyde as trypsin inhibitor up to now. Both R- and S-2-hydroxy-4-(4-hydroxy-phenyl) butanoic acid (Hhpba) were prepared and incorporated into the total synthesis of nostosin B, respectively. Careful comparison of the NMR spectra and optical rotation data of synthetic nostosin B (1a and 1b) with the natural product led to the unambiguous identification of
Nostosins A和B是从Nostoc sp。的亲
水性
提取物中分离得到的。伊朗具有优良的胰
蛋白酶抑制活性的菌株。迄今为止,Nostosin A是最有效的天然三肽醛作为胰蛋白酶抑制剂。分别制备了R-和S-2-羟基-4-(
4-羟基-苯基)
丁酸(Hhpba),并将其分别掺入了诺斯托菌素B的总合成中。仔细比较合成的Nossin B(1a和1b)与
天然产物的NMR光谱和旋光度数据,可以明确鉴定Hhpba片段的R-构型,并与真实样品共进样进一步证实了这一点。使用反相柱和手性AD-RH柱进行HPLC检测。