Hantzsch Synthesis of Pyrazolo[1‘,2‘:1,2]pyrazolo[3,4-<i>b</i>]pyridines: Partial Agonists of the Calcitonin Receptor
作者:Eric E. Boros、David J. Cowan、Richard F. Cox、Makda M. Mebrahtu、Michael H. Rabinowitz、James B. Thompson、Lawrence A. Wolfe
DOI:10.1021/jo050370b
日期:2005.6.1
prevention of osteoporosis. Bicycloeneamine 1 was a useful intermediate in the synthesis of pyrazolopyridine calcitonin receptor partial agonists 2a−f. Dihydropyridines 10a−c were conveniently prepared by reaction of 1 with Knoevenagel adducts 9a−c, or in the case of 10d, by a three component reaction with 1, β-ketoester 7b, and aldehyde 8c. Oxidation of 10a−d to pyridines 11a−d and subsequent amide formation
小分子降钙素受体激动剂在治疗和预防骨质疏松症中具有潜在的用途。在合成吡唑并吡啶降钙素受体部分激动剂2a - f时,双环烯胺1是有用的中间体。通过使1与Knoevenagel加合物9a - c反应,或在10d的情况下,通过与1,β-酮酸酯7b和醛8c的三组分反应,可以方便地制备二氢吡啶10a - c。10a - d氧化为吡啶11a- d和随后的酰胺形成,得到标题化合物。