CLERODANE DITERPENES FROM THE BARK OF CASEARIA-TREMULA

Six novel clerodane diterpenes have been isolated from the bark of Cas earia tremula. They were characterized by extensive use of Heteronucle ar Multiple Bond Coherence NMR spectroscopy as rel-18(S),19(R)-diaceto xy-18, 19-epoxy-6(R)-methoxy-2(S)-(2 xi-methylbutanoyloxy) 5(R),8(S),9 (S),10(R)-cleroda-3,13(16),14-triene, rel-18(S),19(R)-diacetoxy-18,19- epoxy-2(S)-(2 xi-methylbutanoyloxy)- 5(R),8(S), 10(R)-cleroda-3,13(16) ,14-triene, etoxy-18,19-epoxy-2(R)-hexanoyloxy-5(R),8(S),9(S), 10(R)-c leroda-3,13(16),14-triene, xy-5(R),8(S),9(S),10(R)-cleroda-3,13(16),14 -triene and xy-6(R)-hydroxy-2(S)-undecanoyloxy-5(R),8(S),9(S), 10(R)-c leroda-3,13(16),14-triene, rel-18(S), 19(R)-diacetoxy-18,19-epoxy-6(R) -hydroxy 2(S)-(2 y)-5(R),8(S),9(S),10(R)-cleroda-3,13(16),14-triene an d ),19(R)-diacetoxy-18,19-epoxy-6(R)-hydroxy-2(S)-(3 xi-hydroxyoctanoy loxy)-5(R),8(S),9(S), 10(R)-cleroda-3,13(16),14-triene.