The key intermediate to squalamine, (5alpha,7alpha,24R)-7,24-dihydroxy-cholestan-3-one, was synthesized from the 3-O-acetyl-24R,25-dihydroxy derivative of desmosterol via 10 steps in 16% overall yield and squalamine was also prepared via two further steps in 7.4% total yield from the desmosterol derivative.

中文翻译：

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从去甾醇中正式合成角鲨胺。

角鲨胺的关键中间体（5alpha，7alpha，24R）-7,24-二羟基胆甾烷-3-一是由去氧甾醇的3-O-乙酰基-24R，25-二羟基衍生物经10个步骤以16％合成的还通过另外两个步骤制备了总收率和角鲨胺，从去甾醇衍生物的总收率为7.4％。