Pharmacologic suppression of estrogens with aminoglutethimide as treatment of advanced breast carcinoma

PBr3-mediated [5 + 1] annulation of α-alkenoyl-α-carbamoyl ketene-S,S-acetals: access to substituted pyridine-2,6(1H,3H)-diones

Facile and efficient synthesis of substituted pyridine-2,6(1H,3H)-diones via an intramolecular [5 + 1] annulation of readily available α-alkenoyl-α-carbamoyl ketene-S,S-acetals mediated by phosphorus bromide under very mild is developed.

Pyridoglutethimide [3-ethyl-3-(4-pyridyl)-piperidine-2,6-dione], an analogue of aminoglutethimide. Metabolism and pharmacokinetics

Pyridoglutethimide [3-ethyl-3-(4-pyridyl)piperidine-2,6-dione] has been developed as an analogue of aminoglutethimide [3-(4-aminophenyl)-3-ethyl-piperidine-2,6-dione] possessing specific aromatase activity with potency comparable to aminoglutethimide. This study investigates the pharmacokinetics of pyridoglutethimide in the rat and the rabbit: the plasma half-life is 6 hr in the rat and 16.4 hr in the rabbit. The sole metabolite found in urine (rat) and plasma (rat and rabbit) is pyridoglutethimide N-oxide.

Beneficial response to pituitary ablation following aminoglutethimide

Twenty-five postmenopausal women with advanced carcinoma of the breast, who were treated initially with aminoglutethimide alone (14 patients) or combined with tamoxifen (11 patients) had, on relapse or failure of treatment, a pituitary ablation performed. Initial therapy had produced a complete response in one patient, a partial response in 7, disease stasis in 6 but was without benefit in 8 patients. A further three patients were intolerant of aminoglutethimide therapy. Ten of these 25 patients benefited from subsequent pituitary ablation (1 complete response, 4 partial responses and 5 disease stasis), both local and distant sites of disease being influenced by this further therapy. Experience is also reported of 10 patients with advanced breast cancer who were treated initially by pituitary ablation and then subsequently received aminoglutethimide therapy. None responded. It is concluded that pituitary ablation should be considered for patients with progressive disease following aminoglutethimide therapy, irrespective of the therapeutic response to aminoglutethimide.

Metabolism of 4-hydroxyandrost-4-ene-3,17-dione by rat hepatocytes

4-[14C]HAD was rapidly metabolized (99% after 5 min) by hepatocytes from phenobarbital-treated rats. An array of phase I metabolites was formed, variously involving one and two reductions, hydroxylation, hydration and hydroxylation plus one or two reductions. Some of the metabolites were identified by synthesis and others tentatively by mass spectrometry. After 10 min, approximately 30% of the original radioactivity was present in HAD glucuronide and, after 15 min, approximately 60% was present in the total glucuronide fraction which contained several components. Only one of the phase I metabolites (2-hydroxy-HAD) exhibited significant aromatase inhibitory activity (45% of that of HAD).