Two New Anti-Tumor Promoting Serratane-Type Triterpenoids from the Stem Bark of Picea jezoensis var. jezoensis

Abstract

Two new serratane-type triterpenoids, 1 and 2, were isolated from the stem bark of Picea jezoensis Carr. var. jezoensis (Pinaceae). Their structures were determined to be 3β-methoxyserrat-13-en-21β-ol (1) and 13β, l4β-epoxy-3β-methoxyserratan-21β-ol (2) on the basis of spectroscopic methods and partial syntheses. Compounds 1 and 2 and their acetates were screened as potential anti-tumor promoters by using the in vitro short-term 12-O-tetradecanoylphorbol 13-acetate (TPA)-induced Epstein-Barr virus early antigen (EBV-EA) activation assay. IC₅₀ value evaluation showed that compound 1 was more effective than others. In addition, compounds 1 and 2 were examined for anti-tumor promoting activities in a two-stage carcinogenesis assay of mouse skin tumors induced by 7,12-dimethylbenz[a]anthracene (DMBA) as an initiator and TPA as a promoter. Compounds 1 and 2 exhibited significant anti-tumor promoting effects on mouse skin carcinogenesis.

Key words

3β-Methoxyserrat-13-en-21β-ol - 13β,14β-epoxy-3β-methoxyserratan-21β-ol - Picea jezoensis var. jezoensis - Pinaceae - 2D NMR - in vitro EBV-EA activation assay - in vivo two-stage mouse skin carcinogenesis test

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