Steroid esters preparation
AssigneeAB Leo
InventorsAnders R. Stamvik, Sten K. Kristensson, Karl-Erik Lundvall
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Abstract
This invention relates to an improved steroid ester synthesis in which carbodiimides and catalytic amounts of 4-(tertiary amino)-pyridines, in combination with acid catalysts, are used as condensing agents, resulting in pure, non discolored compounds in high yields.
Claims19
A process for the preparation of a steroid carboxylic acid ester of high purity and in improved yield and colour, comprising reacting in an inert organic solvent, which is nonreactive with the reactants and the reaction products under the condition of the reaction, a carboxylic acid, a steroid hydroxyl compound which has a cyclopentanophenanthrene carbon-carbon skeleton and contains up to a maximum of 40 carbon atoms, and which is selected from the group consisting of steroid primary or secondary alcohols and phenols, and a carbodiimide, in the presence of a combination of a 4-(tertiary amino)-pyridine and a strong acid.
Dependencies are inferred from the claim text.