39833-17-5Relevant academic research and scientific papers
Synthesis of 17-(2-Methoxy-3-oxazolin-4-yl)-, 17-(3-Oxazolin-4-yl)-, and 17-(2-Oxazolin-4-ylidene)-Substituted Steroids and Their Use as Precursors of Corticosteroids
Leusen, Daan van,Batist, Jacobus N. M.,Lei, Jia,Echten, Erik van,Brouwer, Antoon C.,Leusen, Albert M. van
, p. 5650 - 5657 (1994)
17-(Isocyanotosylmethylene)steroids 4 are useful intermediates in the conversion of 17-oxosteroids into 17-(hydroxyacetyl)steroids.The 21-CH2OH group is effectively introduced by a base-mediated reaction of compounds 4 with formaldehyde and MeOH to give 17-(2-methoxy-3-oxazolin-4-yl)derivatives 12, which by acid hydrolysis give 17-(hydroxyacetyl)steroids 10 and 16 in high yields.Partial hydrolysis of the same oxazoline derivatives 12 provides the 17-(hydroxyacetyl) cortico side chain of 13 equipped with a formyl-protected hydroxy group. 3-Oxazolinyl and 2-oxazolinylidene steroid derivatives 19, 20, and 21, without a 2-methoxy substituent, are discussed as alternatives of 12.
