Nigellidine

The indazole alkaloid Nigellidine (269) (Scheme 88) which was described as a zwitterion, was detected in the seeds of Nigella saliva L. (Ranunculaceae) (95TL1993), which is an erect annual plant found in South Asia and is widely cultivated. The seeds are commonly believed to have carminative, stimulatory and diaphoretic properties (75PHA2759). An X-ray single crystal analysis was performed on the methyl chloride. It is... 

The structure of nigellidine (Section 12.10.15.1) was unambiguously determined by X-ray diffraction of its methyl iodide and methyl chloride salts. The methyl chloride salt gave better data, and its crystals formed the triclinic space group PI with a = 9.334(3), b = 14.050(4), c = 14.862(4) A, a = 81.83(2)°, f3 = 74.80(2)°, and 7 = 87.26(2)°. The methyl attached to O-l comes from the methyl chloride used for the salt formation the natural product exists as a zwitterion <1995TL1993>. 

Scheme 16.43 C-H arylation of indazoles synthesis of YD-3, YC-1, and nigellidine hydrobromide.

This catalytic reaction was successfully applied to the C—H arylation of indazole 190 with4-bromoanisole to synthesize a biologically active compound, nigellidine hydrobromide (Scheme 16.43b). 

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