Total synthesis and biological evaluation of C-nor-D-homo Steroids

c -no -d -homo类固醇（6-6-5-6环状系统）是一种具有抗肿瘤和抗糖尿病活性的有趣生物学特性的天然产物。尽管它们在生物学和医学上很重要，但文献中只描述了几种合成类固醇。在这项建议的框架内，将建立一个一般性条目。从(-)-香樟醛和现成的(+)- wieland - miescher酮开始，以会聚的方式合成开链前体，在随后的反应中，以Nazarov环化为关键步骤，一步转化为c -no - d- homo类固醇。我们的努力将为这类类固醇及其非天然类似物的普遍进入开辟道路。合成的化合物将使用gli报告试验进行生物学评价。

C-nor-D-homo steroids (6-6-5-6 annulated systems) are natural products with interesting biological properties ranging from anti-tumoral to anti-diabetic activities. Despite of their importance in biology and medicine only a few synthetic entries to this steroids were described in the literature. In the frame of this proposal a general entry will be established. Starting from (-)-citronellal and the readily available (+)-Wieland-Miescher ketone, in a convergent approach, an open chain precursor will be synthesized which in a subsequent reaction, using the Nazarov cyclisation as a key step, will be transformed in one step to the C-nor-D-homo steroid. Our efforts will open the way to a general entry to this class of steroids and their non natural analogs. The synthesized compounds will be biologically evaluated using the Gli-reporter assay.