Structure elucidation and spectral assignment of analogs of navelbine® (8′-noranhydrovinblastine)

During the development of the bis-indole alkaloid anticancer drug Navelbine(R) (vinorelbine), several chemical degradants of the drug were isolated and identified. These included 7'-nor-6',9'-secovinorelbine (7',8'-bisnor-6',9'-secoanhydrovinblas tine) and 4-deacetyl-8'-vinorelbine (4-deacetyl-8'-noranhydrovinblastine). The elucidation of the structure of 7'-nor-6',9'-secovinorelbine is described; the assignment of the proton and carbon spectra of both compounds is contrasted to the shift assignments of Navelbine.