Design and synthesis of novel D-ring fused steroidal heterocycles
作者:Bao-Le Zhang、En Zhang、Lu-Ping Pang、Li-Xing Song、Ya-Fei Li、Bin Yu、Hong-Min Liu
DOI:10.1016/j.steroids.2013.07.006
日期:2013.12
Using dehydroepiandrosterone as the starting material, we have synthesized a series of steroid analogs possessing a D-ring fused with heterocycles which are pyridine, imidazo [2,1-b]thiazoles or substituted thiazole imines. All the final structures are first reported and identified by NMR and MS spectroscopys, the yields of these products are moderate to good and the reaction conditions are mild. The
β-halo α,β-unsaturated aldehydes by a microwave-assisted Knoevenagel reaction. The β-halo-α,β-unsaturated aldehydes were, in turn, efficiently synthesized from the corresponding ketones by a Vilsmeier formylation reaction. The protocol was used to synthesize several novel steroidal and nonsteroidal fused 2-aminopyridine derivatives. 2-Aminopyridines were synthesized from β-halo α,β-unsaturated aldehydes