Results 121 to 130 of about 4,314 (176)

Penicillanic acid derivatives in the canine prostate

Prostate, 1980
AbstractDistribution of ampicillin, amoxicillin, bacampicillin, mecillinam, pivmecillinam, carbenicillin, and carbenicillin indanyl sodium was studied in the canine prostate, prostatic interstitial fluid, and prostatic secretion. All seven antibiotics were found in higher concentrations in the prostatic interstitial fluid than in the prostatic ...
O S Nielsen, P O Madsen
exaly   +3 more sources

Gas Chromatography of Penicillin and Penicillanic Acid Esters

Nature, 1964
WHILE preparing and investigating the properties of penicillanic acid (IVa) and its derivatives, we have found that it is possible to separate esters of penicillins and of penicillanic acids by gas chromatography. 6-Chloro-(IIa) and 6-bromo-penicillanic acid (IIa) were prepared by diazotization of 6-aminopenicillanic acid1 (III) in dilute hydrochloric ...
E Evrard, H Vanderhaeghe
exaly   +3 more sources

Equilibration of penicillanic acid derivatives

Challenge, 1971
Certain 6β-substituted penicillanic acid esters undergo equilibration with the corresponding 6α-isomers in the presence of 1,5-diazabicyclo[4,3,0]non-5-ene at room temperature: the equilibrium constant depends upon the steric requirement of the 6-substituent and upon the solvent.
R J Stoodley
exaly   +2 more sources

Cyclic sulphamidite analogues of penicillanic acid

Journal of the Chemical Society Chemical Communications, 1989
Diastereoisomeric analogues of penicillanic acid have been synthesised in which the β-lactam ring is replaced with the 2-oxo-1,2,3-oxathiazolidine (cyclic sulphamidite) ring; ring fusion greatly increases the chemical reactivity of the 2-oxo-1,2,3-oxathiazolidine ring to nucleophilic attack.
Bill K. Cuthbert, Gordon Lowe
exaly   +2 more sources

Kinetic studies on the carboxylation of 6-amino-penicillanic acid to 8-hydroxy-penillic acid

Process Biochemistry, 1997
Abstract The carboxylation in aqueous solution of 6-amino-penicillanic acid (6-APA) to 8-hydroxy-penillic acid (8-HPA) was studied at 25°C and pH 6·5. During sparging with either a citrate buffer or a chemically defined cultivation medium containing 6-APA with mixtures of carbon dioxide and air (2·7–41% (v/v) CO 2 ), the kinetics for conversion of 6 ...
Dick Schipper, Jens Nielsen, J Villadsen   +2 more
exaly   +2 more sources

Structure of the sodium salt of penicillanic acid

Acta Crystallographica Section C: Crystal Structure Communications, 1988
B Norberg, G Evrard, F Durant
exaly   +3 more sources