Pfizer Corporation

Kelvin S Holdom

Edmund W Hafner

S Edward Lee

Hiroshi Maeda

Junsuke Tone

Stephen Paul Gibson

Alexander C Goudie

John C Ruddock

John D Bu'Lock

Martin R Jefson

John D Bu'lock

Norman Winskill

The invention provides novel compounds having the formula: ##STR1## wherein R when taken individually is H; R.sup.1 when taken individually is H or OH; R and R.sup.1 when taken together represent a double bond;

Antiparasitic agents and process for their preparation

Streptomyces avermitilis lacking branched-chain amino acid transaminase activity and/or branched-chain 2-oxo acid dehydrogenase activity, methods for preparation thereof, and use thereof to produce natural and non-natural avermectins useful as parasiticides.

Process for production of avermectins

Streptomyces avermitilis lacking branched-chain 2-oxo acid dehydrogenase activity and avermectin B O-methyltransferase activity, method for preparation thereof, and use thereof to produce natural and non-natural B avermectins useful as parasiticides.

Process for production of B avermectins

Cultures for production of B avermectins

Process for production of avermectins and cultures therefor

Process for the preparation of antiparasitic agents

Cultures for production of avermectins

Antiparasitic agents

Non-natural demethylavermectins useful as parasiticides and process therefor.

Non-natural demethylavermectins compositions and method of use

A new glycopeptide antibiotic UK-68,597 can be prepared by submerged aerobic propagation in aqueous nutrient media of Actinoplanes sp. ATCC 53533. The antibiotic and its cationic salts are active against a variety of microorganisms and are effective in controlling coccidiosis, enteritis, swine dysentery and theileriosis as well as being effective in promotion of growth and/or improving efficiency of feed utilization in poultry, swine and ruminants.

Fermentation process for glycopeptide antibiotic

New glycopeptide antibiotic

The antibiotic of the formula: ##STR1## wherein R is ##STR2## The antibiotic is useful for the treatment of swine dysentery and for promoting growth and/or increasing the efficiency of food utilization in poultry, swine and ruminants.

Antibiotic produced by fermentation

Aconitic acid, an unsaturated tricarboxylic acid, is obtained by fermentation of an aconitic acid-accumulating strain of Aspergillus terreus or Aspergillus itaconicus, under aerobic conditions, in a carbohydrate-containing medium, followed by isolation of the aconitic acid or a salt thereof. A preferred aconitic acid-accumulating microorganism is the strain of Aspergillus terreus which is on deposit in the Culture Collection of the Commonewealth Mycological Institute at Kew, Surrey, United Kingdom, under Accession No. CMI CC 281924.

Growing community of inventors

Ramsgate, United Kingdom

Kelvin S Holdom