Two new cneorubin related diterpenes from the leaves of Guarea guidonia (Meliaceae)

Two new and two known cneorubin related diterpenes were isolated from the leaves of Guarea guidonia (Meliaceae). One of the new diterpenes has the unusual trans bicyclo[5.1.0]octane ring system. The structures were elucidated by spectral data. The analysis of the NMR spectra of the known diterpenes allowed the reassignment of their NMR data.

Guarea guidonia; Meliaceae; diterpenes; cneorubinanes; NMR data

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