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

A novel process for the preparation of biotin is disclosed wherein said process employs inexpensive starting materials and reagents resulting in the obtention of biotin devoid of the biologically inactive stereoisomers.

Peptides having adrenocorticotropic hormone activity and resin peptides useful in preparation of such peptides, particularly such peptides having asparagine at the carboxyl end thereof and more particularly such peptides having from 19 to 25 amino acids in their amino acid chains. The invention further involves new processes for the preparation of such peptides.

A procedure for the synthesis of biotin is disclosed whereby unsaturated diacylated biotin precursors are catalytically hydrogenated with the substantial absence of sulfur poisoning. The hydrogenation procedure dislcosed herein results in optically pure biotin.

A novel process for the preparation of biotin is disclosed wherein said process employs inexpensive starting materials and reagents resulting in the obtention of biotin devoid of the biologically inactive stereoisomers.

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.

The synthesis of 25-hydroxycholesterol from animal bile starting materials in which hyodeoxychloic acid or an ester thereof is converted to the 3.beta.-hydroxy-5-cholenic acid alkyl ester, and then converted to 3.beta.-hydroxy-25-cyano-5-cholene by a series of steps in which the sterol nucleus is stablized by use of a 3.alpha.,5.alpha.-bridge sometimes called an i-steroid configuration, and the carbon chain then extended from the carbon at the 24-position to a cyanide group at the 25-position. T...

A mixed solid phase-solution phase synthesis for somatostatin which combines the speed of conventional solid phase synthesis with the advantage of solution phase isolation and purification techniques.

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.

Resin peptides useful in the preparation of peptides having biological activity, and particularly such resin peptides containing R-CH.sub.2 -Phe-Glu at one end of an amino acid chain, R being the resin and Phe and Glu being the residues of the amino acids phenylalanine and glutamic acid; and processes for the preparation of such resin peptides. Resin peptides are disclosed which contain amino acid chains identical with the amino acid chains of natural peptides having biological activity. Other r...