Vitamin D deficiency might cause a wide variety of human disorders. As a prerequisite for appropriate diagnosis and therapy, medicinally relevant vitamin D metabolites have to be assayed most accurately and with high specificity. It has been demonstrated, that vitamin D conjugates, linked via a hydroxyl group at C11, might be promising for the development of highly specific antibodies to be employed in competitive protein binding assays. The connective synthesis of 3-TBDMS-11α,25-dihydroxyvitamin D3 and D2 ethers in 500 mg scale, starting from vitamin D2, is described. For installation of a hydroxyl group at C11 a sequence of Pd(OAc)2 mediated oxidation of an enone, epoxidation and subsequent epoxide ring opening was applied to obtain a suitable CD-ring precursor, that was connected with an A-ring diphenylphosphine oxide by Wittig-Horner reaction. Finally, an appropriate side chain was installed, respectively.

中文翻译：

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有效合成3-TBDMS-11α，25-二羟基维生素D3和D2醚。

维生素D缺乏症可能导致多种人类疾病。作为适当诊断和治疗的先决条件，必须最准确，高度特异性地测定与医学相关的维生素D代谢产物。已经证明，通过C11处的羟基连接的维生素D缀合物对于开发用于竞争性蛋白质结合测定中的高特异性抗体可能是有希望的。描述了从维生素D2开始的500毫克规模的3-TBDMS-11α，25-二羟基维生素D3和D2醚的连接合成。为了在C11处安装羟基，使用Pd（OAc）2介导的烯酮的氧化，环氧化和随后的环氧化物开环的序列，以获得合适的CD环前体，其通过以下方式与A环二苯基膦氧化物连接： Wittig-Horner反应。