Cimetidine analog

Drugs that may interact with zalcitabine include antacids, chloramphenicol, cisplatin, dapsone, didanosine, disulfiram, ethionamide, glutethimide, gold, hydralazine, iodoquinol, isoniazid, metronidazole, nitrofurantoin, phenytoin, ribavirin, vincristine, cimetidine, metoclopramide, amphotericin, aminoglycosides, foscarnet, antiretroviral nucleoside analogs, pentamidine, and probenecid. 

Acid hydrolysis of the nitrile in the API cimetidine leads to the corresponding amide which then undergoes further degradation through loss of the CONH2 moiety via a pathway that is analogous to a (3-keto acid decarboxylation (Fig. 30) (47). 

The preparation of the pyridyl analogs of the imidazolyl compounds of the type of cimetidine are discussed in the patent cited below. 

Bum JH, Finney DJ, Goodwin LG (eds) (1952) Biological standardization, Chapter XVII, Gastric secretion. Oxford University Press, London, pp 332-334 Gallo-Torres HE, Kuhn D, Witt C (1979) A method for the bioassay of antisecretory activity in the conscious rat with acute gastric fistula Studies with cimetidine, somatostatin, and the prostaglandin E2-analog RO 21-6937. J Pharmacol Meth 2 339-355... 

Stimulation of the H2 receptors elicits a variety of responses, the most widely studied of which is gastric acid secretion from the parietal cells of the gastric glands. However, many other effects mediated by H2 receptors are manifested in peripheral tissues. These include the positive chronotropic action in the auricular muscle, the inotropic action in the ventricular muscle, and the hpolytic effect in fat cells. In addition, the extensive use of cimetidine has led to the synthesis and marketing of more specihc and efhcacious analogs (see also Figure 34). 

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