Enzymatic Synthesis of Dehydro Cyclo(His–Phe)s, Analogs of the Potent Cell Cycle Inhibitor, Dehydrophenylahistin, and Their Inhibitory Activities toward Cell Division
作者:Hiroshi KANZAKI、Satohiro YANAGISAWA、Teruhiko NITODA
DOI:10.1271/bbb.68.2341
日期:2004.1
Cyclo(His–Phe) was effectively converted to its dehydro derivatives by the enzyme of Streptomyces albulus KO-23, an albonoursin-producing actinomycete. Two types of dehydro derivatives were isolated from the reaction mixture and identified as cyclo(ΔHis–ΔPhe) and cyclo(His–ΔPhe). This is the first report on cyclo(His–ΔPhe) and the enzymatic preparation of both compounds. Cyclo(ΔHis–ΔPhe), a tetradehydro cyclic dipeptide, exhibited a minimum inhibitory concentration of 0.78 μmol/ml inhibitory activity toward the first cleavage of sea urchin embryos, in contrast to cyclo(His–ΔPhe) that had no activity. The finding that the isoprenylated derivative of cyclo(ΔHis–ΔPhe), dehydrophyenylahistin, had 2,000 times higher activity than cyclo(ΔHis–ΔPhe) indicates that an isoprenyl group attached to an imidazole ring of the compound was essential for the inhibitory activity.
环(组氨酸-苯丙氨酸)被白链霉菌KO-23的酶有效转化为脱氢衍生物,这是一种产生白链霉素的放线菌。从反应混合物中分离出两种脱氢衍生物,并鉴定为环(Δ组氨酸-Δ苯丙氨酸)和环(组氨酸-Δ苯丙氨酸)。这是关于环(组氨酸-Δ苯丙氨酸)和两种化合物的酶促制备的首次报道。环(Δ组氨酸-Δ苯丙氨酸)是一种四脱氢环状二肽,对海胆胚胎第一次分裂的抑制活性最低抑制浓度为0.78微摩尔/毫升,而环(组氨酸-Δ苯丙氨酸)则没有活性。环(Δ组氨酸-Δ苯丙氨酸)的异戊烯基衍生物脱水苯丙氨酰基白链霉素的活性比环(Δ组氨酸-Δ苯丙氨酸)高2000倍,这一发现表明,异戊烯基连接到化合物的咪唑环上对于抑制活性至关重要。