Abstract: A novel process is described for preparation of biotin comprising preparation of substituted 3H, 5H-imidazo[1,5c]tetrahydro thiazoles by contacting the boron trifluoride adduct of an appropriate thiazoline with the metallic derivative of an ester enolate, reducing the ester, hydrolyzing the thiazolidine moiety and hydrolyzing or oxidizing the resultant compound. Intermediates obtained in the preparation of biotin by the above process and alternate procedures for preparing said intermediates are also presented. A novel process for preparation of d-biotin is also given.
Abstract: Corrosion resistance of stainless steel powder moldings is improved by combining the powder before molding with about 8 to 16% by weight of an additive consisting essentially of about 2 to 30% by weight of tin and 98 to 70% by weight of copper and/or nickel. Stainless steel moldings are prepared by compacting the powder at high pressure and heating to sintering temperature.
Abstract: 1-Alkyl-6,8-difluoro-7-heterocyclic-1,4-dihydroquinol-4-one 3-carboxylic acids having antibacterial activity are prepared by conventional cyclization methods.
Type:
Grant
Filed:
April 4, 1985
Date of Patent:
January 13, 1987
Assignee:
Pfizer, Inc.
Inventors:
Paul J. Gilligan, Paul R. McGuirk, Michael J. Witty
Abstract: A novel process is described for preparation of biotin comprising preparation of substituted 3H, 5H-imidazo[1, 5c]tetrahydro thiazoles by contacting the boron triflouride adduct of an appropriate thiazoline with the metallic derivative of an ester enolate, reducing the ester, hydrolyzing the thiazolidine moiety and hydrolyzing or oxidizing the resultant compound. Intermediates obtained in the preparation of biotin by the above process and alternate procedures for preparing said intermediates are also presented. A novel process for preparation of d-biotin is also given.
Abstract: Calcium-aluminum briquettes comprising a mechanically compressed mixture of 65 to 80% by weight of calcium granules and 20 to 35% by weight of aluminum granules are added to molten lead to obtain a lead alloy containing about 0.1% by weight of calcium and 0.03% by weight of aluminum.
Abstract: High molecular weight caprolactone polymers are coated on surgical sutures to improve suture properties such as smooth surface, single knot slipdown, two throw knot slipdown for repositioning, and three throw knot security.
Abstract: 1-Substituted-6-fluoro-7-aryl-(8-fluoro)-1,4-dihydroquinol-4-one 3-carboxylic acids having antibacterial activity are prepared by reacting the corresponding alkyl 1-substituted-6-fluoro-7-bromo-(8-fluoro)-1,4-dihydroquinol-4-one-3-carbox ylate with an arylmetallic compound and hydrolyzing the ester formed.
Type:
Grant
Filed:
December 6, 1984
Date of Patent:
November 18, 1986
Assignee:
Pfizer Inc.
Inventors:
Paul J. Gilligan, Paul R. McGuirk, Michael J. Witty
Abstract: A surgical suture made of a polymer filament having the "hard" elastic properties of reversible elasticity and retention of diameter on stretching.
Abstract: The adherence of a bioactive glass coating to a metal substrate is improved by applying said glass to said substrate in admixture with at least one of cobaltic oxide, cobaltous oxide, nickel oxide or manganese oxide, and firing the coated substrate at at least about 730.degree. C.
Abstract: Gases entrapped in a metal assembly are exhausted through a vent closed off by a metal or metal alloy which has a melting point below the temperature at which said assembly is hot rolled. The metal assembly is designed to bond dissimilar metals on hot rolling.
Abstract: A novel process is described for preparation of biotin comprising preparation of substituted 3H, 5H-imidazo[1, 5c]tetrahydro thiazoles by contacting the boron trifluoride adduct of an appropriate thiazoline with the metallic derivative of an ester enolate, reducing the ester, hydrolyzing the thiazolidine moiety and hydrolyzing or oxidizing the resultant compound. Intermediates obtained in the preparation of biotin by the above process and alternate procedures for preparing said intermediates are also presented. A novel process for preparation of d-biotin is also given.