64603-72-1Relevant academic research and scientific papers
Approaches to combinatorial synthesis of heterocycles: Solid phase synthesis of pyridines and pyrido[2,3-d]pyrimidines
Gordeev, Mikhail F.,Patel, Dinesh V.,Wu, Jie,Gordon, Eric M.
, p. 4643 - 4646 (1996)
An efficient solid phase synthesis of diverse pyridines and pyrido[2,3-d]pyrimidines is described. O-Immobilized keto esters 2 react with aldehydes to afford Knoevenagel derivatives 3. These undergo Hantzsch-condensation with α-oxo enamines to generate 1,4-dihydropyridines 4 that are oxidized with CAN to produce immobilized pyridines 5. The method has been extended to synthesis of fused pyrido[2,3-d]pyrimidines employing 6-aminouracils as the α-oxo enamine component. The course of the reaction on solid phase was studied by gel-phase 13C NMR spectroscopy. The synthesis is designed to be amenable for combinatorial libraries preparation.
Biotransformation of nitrendipine in rat, dog, and mouse
Scherling,Karl,Ahr,Kern,Siefert
, p. 1009 - 1021 (2007/10/02)
14C-Labelled Nitrendipine (Bay e 5009; Baypress, Bayotensin; CAS 39562-70-4) was administered by the oral and intraduodenal route to rats, dogs, and mice (oral dosing only) to elucidate the biotransformation pathways in these three species. The drug was extensively metabolized: 20 biotransformation products were identified by comparison with synthetic reference compounds using two-dimensional TLC, HPLC, GC/radio-GC, combined GC/MS (EI-, CI-mode), FAB-MS, and 1H-NMR-spectroscopy. The metabolites identified accounted for approx. 72 to 73% of the dose administered in rats and dogs (bile and urine) and 48 to 56% in male and female mice (urine only). Based on the structures identified the following biotransformation reactions occurred: Dehydrogenation of the 1,4-dihydropyridine (primary metabolic step), oxidative ester cleavage as further basic biotransformation reaction (also at the dihydropyridine state), hydroxylation of the methyl groups in 2- or 6-position as separated and important metabolic reaction (at the dihydropyridine as well as pyridine state), reduction of the aromatic nitro group (important only in mice) and subsequent acetylation (dog only), and glucuronidation as phase II reaction forming ether and ester type glucuronides.
