Pyridazinones. 3. Synthesis, antisecretory, and antiulcer activities of 2-cyanoguanidine derivatives
摘要:
3(2H)-Pyridazinone derivatives having a 2-cyanoguanidine moiety, as well as a sulfur or an oxygen atom in the alkylene side chain, were synthesized and evaluated for gastric antisecretory and antiulcer activities. The key intermediates, free amines having a thioether linkage, were synthesized by the reaction of 2-(omega-chloroalkyl) derivatives with cysteamine, while other intermediates having an ether linkage were synthesized from 2-(omega-chloroalkyl)oxymethyl derivatives. These free amines were converted via the 3-cyano-2-methyl-1-isothiourea derivatives into the desired 2-cyano-3-substituted-1-guanidine derivatives. All compounds synthesized were evaluated for gastric antisecretory activity in the pylorus-ligated rat by the method of Shay, and selected compounds were evaluated in the stress-induced ulcer test in rat. Structure-activity relationships are discussed. The molecular features for the best activities are a phenyl group in the C-6 position of the 3(2H)-pyridazinone ring, a four-atom chain length between the 3(2H)-pyridazinone ring and the 2-cyanoguanidine moiety, and a thioether rather than an ether linkage. Among them, compound 14, 2-[[[2-(2-cyano-3-methyl-1-guanidino)ethyl]thio]methyl]-6-phenyl-3 (2H)-pyridazinone, had the most potent antisecretory and antiulcer activities. These compounds are neither histamine H2 receptor inhibitors nor anticholinergic agents.
A number of 2-phenoxyalkylaminoalkyl- and 2-[1,4]benzodioxanylmethylaminoalkyl-3(2H)-pyridazinones were synthesized and tested for hypotensive and antihypertensive activity as well as for alpha-1- and alpha-2-adrenoceptor binding affinities. Some derivatives, eg 5.5, 5.9, 5.12, 6.4 and 6.10, showed strong hypotensive/antihypertensive effect and high affinity for alpha-2- and alpha-1-adrenoceptors. Compound 5.5 was selected for clinical study. In its mode of action a potassium channel opening activity may also be involved.
Phase-Transfer Catalyzed<i>N</i>-Alkylation of 3(2<i>H</i>)-Pyridazinones (3-Oxo-2,3-dihydropyridazines)
作者:Toshihiro Yamada、Masahiko Ohki
DOI:10.1055/s-1981-29552
日期:——
YAMADA, TOSHIHIRO;OHKI, MASAHIKO, SYNTHESIS, BRD, 1981, N 8, 631-633
作者:YAMADA, TOSHIHIRO、OHKI, MASAHIKO
DOI:——
日期:——
YAMADA, TOSHIHIRO;NOBUHARA, YOUICHI;SHIMAMURA, HIROSHI;TSUKAMOTO, YOSHITS+, J. MED. CHEM., 1983, 26, N 3, 373-381