No abstract

A series of 1-aryl-2-(aminomethyl)cyclopropanecarboxylic acid derivatives were synthesized and evaluated as potential antidepressants. Compounds with the Z configuration were synthesized from 1-aryl-2-oxo-3-oxabicyclo[3.1.0]hexane and those with the E configuration from (E)-1-phenyl-2-(hydroxymethyl)cyclopropanecarboxylic acid. The compounds were evaluated in animal tests designed to reveal potential antidepressant activity and the existence of undesirable side effects. Several derivatives were more active than imipramine and desipramine. On the basis of its activity in pharmacological animal tests of antidepressant activity and its potential lack of side effects, 1-phenyl-1-[(diethylamino)carbonyl]-2- (aminomethyl)cyclopropane hydrochloride, midalcipran (INN), was selected for further development. This compound is currently in phase III clinical evaluation.

Serum kinetics of Doxycycline polyphosphate (DPP) have been studied in dogs after oral administration of 10 mg.kg-1 by measurement of total serum concentration (Ct) of tetracycline derivatives by a chemical assay and active concentration (Ca) by a microbiological method. Kinetics have been studied using a one compartment open model with absorption by oral route. DPP is rapidly absorbed, the peak serum level is reached three hours after absorption and slowly eliminated (elimination half-life = 12 hours). The main differences observed between Ct and Ca kinetics are in the values of the areas under the curves (AUC) and the peak serum level. The values obtained for these parameters for Ca kinetics were found to be 50% of those obtained for Ct, the volumes of distribution being in inverse proportion. These results are in a good agreement with the correlation and linear regression observed between Ca and Ct showing that 55% of total serum Doxycycline possesses immediate antibacterial activity. It is postulated that this difference between Ct and Ca kinetics is essentially a reflection of the ratios of bound and free drug. Similar results were obtained with the finished pharmaceutical form except for a 15% increase of AUC indicating improvement of the bioavailability of the drug.

Thymoxamine hydrochloride administered by mouth to rats at 25 or 100 mg kg−1 was excreted in the urine as the deacetyl and N‐demethyl‐deacetyl metabolites. These were completely sulpho‐ and glucuronoconjugated at 25 mg kg−1 but only partially so at the higher dose. Thymoxamine deacetylation in vitro is catalysed by plasma and hepatic cytosol esterases and the deacetyl metabolite undergoes N‐demethylation catalysed by the cytochrome P 450 hepatic microsome mixed function monooxygenase system. Because of the rapidity of the deacetylation it is concluded that thymoxamine is a prodrug leading in vivo to the active deacetyl thymoxamine.