Process for preparing steroids 7 (alpha) - alcoxicarbonil substituu00ecdos

摘要

Process for preparing steroids 7 244 - alcoxicarbonil substituu00ecdos procedures are described for the conversion of a substrate steroid with a bridge 4.7 - carbonyl in a structure comprising a substituent 7 244 - alcoxicarbonil by reaction of the substrate with a source of group alcu00f3xi, that are at stake. Rivelmente in the presence of a base. Various modifications of the process options are described.The reaction can be carried out at a temperature greater than about 70 198 C, with residence times substantially shorter than are needed at lower temperatures.A target of saponification can be incorporated in the reaction medium to consume free hydroxide compounds, the compound product 7 244 - alcoxicarbonil can be recovered by crystallization, the values of the residual steroid can be recovered from the liquid crystallization origin p Or extraction.The extract can be processed to produce a solution again reduced to a consistency of pulp that steroids may be reequilibrados to produce product steroid 7 244 - alcoxicarbonil replaced additional.Alternatively, the solution again reduced to a consistency of pulp can be recycled to a reactor in which a primary substrate of bridge 4.7 - carbonyl is converted into the product 7 244 - alcoxicarbonil.The process is particularly useful in the preparation of eplerenona, in which an intermediate dicetona comprising a bridge 4.7 - carbonyl reacts with a metu00f3xido alkali metal to produce a compound 11 244 - hydroxy - 7 244 methoxy carbonyl (hidroxiu00e9ster), the group 11a hydroxy is converted into a Gru Po output which is then abstracted to produce a enu00e9ster 30 n 9.11u00acm and enu00e9ster is epoxidized in eplerenona. Also disclosed is a reaction of epoxidau00e7u00e3o conducted at relatively low hydrogen peroxide in relationship to the substrate enu00e9ster.