Abstract: A process for the preparation of calcipotriol at least including: (a) reacting a C-22 phenylsulfonyl derivative of cholecalciferol of Formula 2, wherein R1 and R2 are the same or different and represent hydroxyl protecting groups, with a silyl derivative of alfa-hydroxy aldehyde of Formula 3, wherein R3 represents silyl group of formula Si(R4)(R5)(R6), where R4-R6 are the same or different and represent C1-6 alkyl or phenyl groups, in the presence of a strong organic base in an aprotic solvent, followed by reductive desulfonation of the obtained diastereomeric mixture of alfa-hydroxysulfones with sodium amalgam, removal of the hydroxyl protecting groups, and purification of the product. The process leads to the formation of calcipotriol containing less than 0.3% of the (22Z)-isomer. The obtained calcipotriol is free of mercury traces.

Abstract: A process for the preparation of calcipotriol at least including: (a) reacting a C-22 phenylsulfonyl derivative of cholecalciferol of Formula 2, wherein R1 and R2 are the same or different and represent hydroxyl protecting groups, with a silyl derivative of alfa-hydroxy aldehyde of Formula 3, wherein R3 represents silyl group of formula Si(R4)(R5)(R6), where R4-R6 are the same or different and represent C1-6 alkyl or phenyl groups, in the presence of a strong organic base in an aprotic solvent, followed by reductive desulfonation of the obtained diastereomeric mixture of alfa-hydroxysulfones with sodium amalgam, removal of the hydroxyl protecting groups, and purification of the product. The process leads to the formation of calcipotriol containing less than 0.3% of the (22Z)-isomer. The obtained calcipotriol is free of mercury traces.

Abstract: A process for the preparation of a pharmaceutical-grade anhydrous calcipotriol comprising: (a) dissolving crude calcipotriol having a water content of X% by weight in a first solvent or in a mixture of two or more first solvents, said first solvent or said mixture of two or more first solvents forming an azeotropic system with water, to obtain a solution of crude calcipotriol; (b) obtaining an intermediate calcipotriol by (i) placing said solution of crude calcipotriol under a reduced pressure and evaporating, if X is greater than or equal to 1, or (ii) crystallizing, if X is lower than 1; and (c) re-dissolving said intermediate calcipotriol in a second solvent or a mixture of two or more second solvents, said second solvent being anhydrous, and crystallizing at least once to obtain pharmaceutical-grade anhydrous calcipotriol.

Abstract: Preparation of sulfonyl derivatives of cholecalciferol of Formula 1, wherein R1 is a protective group, preferably a t-butyl(dimethyl)silyl, and R2 is a heterocyclic group, such as a 2-thiazolyl, a 2-benzothiazolyl, a 1-phenyl-1H-tetrazo-5-yl, a 2-pyridyl, a 2-pyrimidynyl, a 1-isochinolinyl, a 1-methyl-2-imidazyl, or a 4-alkyl-1,2,4-triazo-3-yl, comprises the conversion of the hydroxyl derivative of cholecalciferol into the corresponding sulfide followed by its oxidation to the respective sulfone characterized by the use of a hydroxyl derivative of cholecalciferol as a starting material, in which the triene system is protected as a Diels-Alder adduct, and in particular as an adduct with sulfur dioxide of the Formula 2a. Novel are also the derivatives of Formula 3a and 4a, isolated in the process provided by the invention.

Abstract: A process for the preparation of a pharmaceutical-grade anhydrous calcipotriol comprising: (a) dissolving crude calcipotriol having a water content of X % by weight in a first solvent or in a mixture of two or more first solvents, said first solvent or said mixture of two or more first solvents forming an azeotropic system with water, to obtain a solution of crude calcipotriol; (b) obtaining an intermediate calcipotriol by (i) placing said solution of crude calcipotriol under a reduced pressure and evaporating, if X is greater than or equal to 1, or (ii) crystallizing, if X is lower than 1; and (c) re-dissolving said intermediate calcipotriol in a second solvent or a mixture of two or more second solvents, said second solvent being anhydrous, and crystallizing at least once to obtain pharmaceutical-grade anhydrous calcipotriol.

Abstract: The present invention is a process for the preparation of 17?-hydroxy-7?-methyl-19-nor-17?-pregn-5(10)-en-20-yn-3-one (17?-ethynyl-17?-hydroxy-7?-methyl-5(10)-estren-3-one, tibolone) of formula 1, which comprises hydrolysis of 17?-ethynyl-17?-hydroxy-7?-methyl-5(10)-estrene 3,3-cyclic ketals of formula 2, where groups R1, R2, R3 and R4 are hydrogen atoms or alkyl groups, or R1 and R3, taken together with the carbon atoms within the dioxolane ring to which they are attached, form an alicyclic ring fused to the dioxolane ring, with R2 and R4 being hydrogen atoms, or R1 and R3 together with the carbon atoms to which they are attached form an aromatic ring fused to the dioxolane ring, where R2 and R4, taken together, form a chemical bond within said aromatic ring.

Abstract: Disclosed is a process for the preparation of 24-alkyl analogs of cholecalcyferol of Formula 1 having a (5E) or (5Z) configuration, wherein X represents a hydrogen atom, a hydroxy group or an OR1 group, where R1, R2 and R3 may be the same or different and represent groups suitable for hydroxyl protection, and R4 is a C1-6 alkyl chain or a C1-6 cykloalkyl group, optionally substituted with C1-3 alkyl groups, especially for calcipotriol. The invention also provides new intermediates and non-racemic compounds being valuable synthones for the synthesis of pharmacologically active substances.