摘要：

Total syntheses of a set of naturally occurring 3-oxygenated carbazole alkaloids-6-chlorohyellazole,carazostatin,carbazomycins A and B-are described.The key-strategy underlines a highly chemo-and regioselective rhodium-catalyzed [2+2+2] cyclotrimerization between appropriately tailored yne-ynamides and 1-methoxypropyne that is stirred by the interplay of stereoelectronic and steric effects allowing the introduction of four ring substituents of the natural carbazoles within a single step and making the overall syntheses short and efficient.

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