In the synthesis of sterols wherein methoxyethoxymethyl groups in an ether linkage are attached to the nucleus of the sterol to protect the sterol nucleus during other steps of the synthesis and the sterols are thereafter treated to remove the methoxyethoxymethyl groups and set free the hydroxyl groups, the improvement in which the sterols being treated with zinc bromide are held in a methylene chloride solution containing a small amount of an aliphatic alcohol having from 1 to 6 carbon atoms.

This invention provides a process for producing tetrahydrofuran by the reaction of 3-(5'-alkyl-1',3'-dioxane)propionaldehyde and/or 3-(5'-alkyl-1',3'-dioxane)propanol and/or 4-hydroxybutanal with hydrogen in an aqueous medium having a pH between about 0.1 and 5. Maintenance of the reaction medium within the specified acidic range of pH is an important feature of the invention process.

Asymmetric synthesis of optically active 3,7,11-trimethyl-dodecan-1-ol, an intermediate for producing optically active vitamin E, from isovaleraldehyde or prenal including intermediates in this synthesis.

A process is disclosed for preparing racemic and optically pure tryptophans through novel intermediates.

The synthesis of 25-hydroxycholesterol and 1.alpha.,25-dihydroxycholesterol in which the sterol nucleus of an ester of hyodeoxycholic acid is stabilized by protection of the 3 and 6.alpha.-hydroxyl groups with alkyl groups, alkyl ether groups, preferably with the 3.beta.-methoxyethoxymethyl group or with the heterocyclic 2-tetrahydropyran group, then extending the chain from the carbon at the 24-position to a cyanide group at the 25-position and then subjecting the sterol so formed to a series o...

The synthesis of 1.alpha.,25-dihydroxycholesterol, 1.alpha.,25-dihydroxy-7-dehydrocholesterol and 1.alpha.,25-dihydroxycholecalciferol and other sterol derivatives from bile acids. Also the synthesis of 3,6-diketo steroids useful in the production of 1.alpha.,25-dihydroxycholesterol and other sterols which are biologically active or can be converted to biologically active sterols. The invention involves the sterols so produced and the processes by which they are prepared.

Methanol is produced from a carbon monoxide stream by reacting carbon monoxide with steam in a catalytic shift reaction, removing any excess steam and at least part of the carbon dioxide from the shifted gas, reacting the resulting gas over a copper-containing methanol synthesis catalyst at under 300.degree. C., heat exchanging reacted synthesis gas with water under pressure and bringing the resulting hot water into direct heat exchange with the carbon monoxide stream to provide steam for the sh...

A process for synthesizing daunosamine and related compounds is disclosed. Intermediates useful for synthesizing daunosamine, and processes for preparing such intermediates, are also disclosed.

Process for synthesizing the lactone, (dl) 3,3a beta-4,5-6,6a beta-hexahydro-4beta(3-hydroxyl-1-trans-octenyl)-5alpha-hydroxy-2-oxo-2H-c yclopenta[b]furan, a known intermediate for producing prostaglandin E.sub.2 and F.sub.2.alpha. and a process for preparing 11-desoxy and 11-alkyl prostaglandins from dihydroresorcyclic acid.

A process for making zeolite S by reacting an aqueous solution of Na.sub.2 CO.sub.3 and NaHCO.sub.3 with glass, e.g., Pyrex glass. The silica and alumina are furnished by slow dissolution of the glass.