Following studies to define the time course, media, and nutrient parameters for the production of the potent cytotoxic antibiotic staurosporine in Streptomyces staurosporeus, biosynthetic studies of staurosporine with singly- and doubly-labeled radioactive precursors established that either one or two units of tryptophan was incorporated efficiently. From the 13C-nmr spectrum of staurosporine subsequent to stable isotope incorporation experiments, it was established that the aglycone moiety was derived from two units of tryptophan with the carbon skeleton incorporated intact.

From the leaves and stems of Larrea tridentata six new furanoid lignans, compounds 1-6, have been isolated and their structures determined through interpretation of physical and spectroscopic properties. The use of 1D and 2D nOe experiments was of particular importance in assigning the stereochemistry.

The first four members of a new class of natural products, the retrodihydrochalcones, have been isolated from the leaves of Dracaena loureiri. The structures of the loureirins 1-4 were elucidated through interpretation of their spectroscopic data, with particular use being made of the selective INEPT nmr technique.

Complete and unambiguous assignments of the 1H- and 13C-nmr spectra of the potent antitumor antibiotic staurosporine have been accomplished using a combination of one- and two-dimensional nmr techniques, including one-bond and long-range heteronuclear multiple-quantum coherence spectroscopy (HMQC). Staurosporine was found to be highly cytotoxic in the KB and P-388 assays but was inactive in the microtubulin assembly assay.

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