37 日本産フサコケムシの抗腫瘍性マクロライドbryostatin類について : bryostatin 10の単離と構造(口頭発表の部)

抄録

The macrolide bryostatin 1-13 isolated from sea mat Bugula neritina(Bryozoa) exhibit highly potent antineoplastic activity. Bryostatin 1 has been isolated only from the specimen of the Pacific coast (Monterey, America). On the other hand, bryostatin 4 and 5 have been isolated as the main compounds of each Gulf of Florida, Gulf of California and Gulf of Sagami specimens. Investigation has been started to be finding the macrolide bryostatins of the Japanese coast Bugula neritina by use of a new bioassay screening that inhibit cell division of sea urchin egg. The resulting bryostatin 10 as main bioactive compound has been isolated from Gulf of Aomori (ASAMUSHI) and Gulf of Ohzuchi (OHZUCHI) specimens of Bugula neritina. Specially, the yield of bryostatin 10 in ASAMUSHI specimen was 10^<-5>% highly (Scheme 1). The structure of bryostatin 10 has been established to be structure 1 (Fig. 1) by new detailed 1D and 2D NMR (^1H and ^<13>C) techniques such as DEPT, ^1H-^1H COSY, ^1H-^<13>C COSY, HMQC (Fig. 2), HMBC, COLOC and NOESY. By these experiments the perfect chemical shifts of ^1H and ^<13>C of bryostatin 10 structure (1) were obtained (Table 1). Also, the ester group at C-7 has been proved to be the pivalate by mainly HMBC experiment (Previously, the ester was assigned to the isovalerate.). Interesting behavior of ^1H and ^<13>C chemical shifts of bryostatin 10 in exchange of the experimental temperature from R.T. to 50℃ was observed at 3-OH, 2-H, 5-H, 7-H, 30-H, 34-H, etc. Bryostatin 10 exhibits against cell division of sea urchin egg (IC_<50> 1.6×10^<-1>μg/ml) and also against people liver cell PLC/PRF/5 (IC_<50> 7.3×10^<-1>μg/ml). On the other hand, antineoplastic activity (in vitro) against the P-388 lymphocytic leukemia with bryostatin 10 displayed substantial cell growth inhibitory (IC_<50> 1.85×10^<-3>μg/ml), which was similar to the previous result (at America).