Diaryl-substituted ortho-carboranes as a new class of hypoxia inducible factor-1α inhibitors

Diaryl-substituted ortho-carboranes 1 were synthesized from the corresponding alkynes by decaborane coupling under microwaveirradiated conditions with a combination of N,N-dimethylaniline and chlorobenzene. Among the compounds synthesized, 1a and 1d exhibited significant inhibition of hypoxia-induced HIF-1 transcriptional activity. Both compounds similarly suppressed hypoxia-induced HIF-1 alpha accumulation in a concentration-dependent manner without affecting HIF-1 alpha mRNA expression.