Synthesis of 2-hydroxy-2-phenylethylamino derivatives as potential α-adrenergic blocking agents
作者:M. Alvarez、R. Granados、R. Lavilla、M. Salas
DOI:10.1002/jhet.5570220326
日期:1985.5
synthesis of N,N'-bis[6-(2-hydroxy-2-phenylethylamino)hexyl] cystamines 4, and N-(2-hydroxy-2-phenylethyl)-1,6-hexanediamines 6 are described. Compounds 4 were obtained by condensation of the requisite epoxide 2 with 3-(6-aminohexyl)-1,3-thiazolidine followed by dimerization with opening of the thiazolidine ring. A similar method was used for the preparation of compounds 6. In order to prepare 4j (N,N'-bis6-[2-hydroxy-2(3
The synthesis and irreversible alpha-blocking activity in the rat vas deferens of a series of tetra- and diamine disulfides 2-38, structural analogues of benextramine (BHC), are described. All compounds containing a central cystamine moiety displayed an irreversible alpha-adrenergic blockade at concentrations ranging from 10(-4) to 6 X 10(-6)M. Potency was increased in cystamines N,N'-disubstituted with 6-aminohexyl groups, especially when the outer nitrogen atoms bear arylalkyl substituents or are enclosed in a ring. However, N,N,N',N'-tetrasubstituted cystamines were poor blockers. Structural specificity in the outer portion of the tetramine disulfide is low, since many types of substituents gave rise to potent alpha-blockers. Even replacement of the outer amines with nonbasic ethers or amides was observed to maintain irreversible alpha-blockade.
Structure-activity relationships among benextramine-related tetraamine disulfides. Chain length effect on .alpha.-adrenoreceptor blocking activity
作者:Wilma Quaglia、Livio Brasili、Gloria Cristalli、Dario Giardina、Maria T. Picchio、Carlo Melchiorre
DOI:10.1021/jm00117a030
日期:1988.9
Several N'-substituted N,N''-(dithiodi-2,1-ethanediyl)bis(1, omega-alkanediamines) were prepared and evaluated for their blocking activity on alpha-adrenoreceptors in the isolated rat vas deferens and human blood platelets. The results were compared with those obtained for benextramine (N,N''-(dithiodi-2,1-ethanediyl)bis[N'-[(2-methoxyphenyl)-methyl]- 1 ,6- hexanediamine], 10). Bendotramine (N,N''-(dithiodi-2,1-ethanediyl)bis[N'-[(2-methoxyphenyl)- methyl]-1,12-dodecanediamine], 16) proved to be as active as 10 on alpha 1-adrenoreceptors, showing that optimum activity is associated with two carbon chain lengths separating inner from outer nitrogens of tetraamine disulfides. On the other hand, 16 had no activity up to 20 microM at alpha 2-adrenoreceptors. The optimum activity at this receptor subtype was associated with a six to eight carbon chain (10-12). Furthermore, 10 proved to be more selective toward alpha 2-adrenoreceptors whereas 16 was a selective alpha 1-antagonist. The tetraamine disulfides were shown also to be potent inhibitors of human platelet aggregation induced by ADP or epinephrine. The potency increased with the carbon chain length. However, the results on platelets did not parallel those found in the rat vas deferens, indicating that differences exist between the alpha-adrenoreceptor subtypes investigated. In conclusion, 10 may be a useful tool in characterizing alpha 2-adrenoreceptors whereas 16 might help in investigating alpha 1-adrenoreceptors.
Melchiorre; Gulini; Giardina, European Journal of Medicinal Chemistry, 1984, vol. 19, # 1, p. 37 - 42
作者:Melchiorre、Gulini、Giardina、et al.
DOI:——
日期:——
Synthesis and α1-antagonist activity of new prazosin- and benextramine-related tetraamine disulfides
Tetraamine disulfides 1-10 were designed by combining the structural features of benextramine, an irreversible alpha(1)/alpha(2)-adrenoceptor antagonist, and prazosin, a selective competitive alpha(1)-antagonist. Their biological profile was assessed by functional and binding assays. In rat vas deferens functional experiments, tetraamine disulfides 1-10 displayed a marked selectivity at alpha(1)-adrenoceptors. Furthermore, they acted as competitive antagonists at alpha(1)-adrenoceptors and weak noncompetitive (irreversible) antagonists at alpha(2)-adrenoceptors. In binding assays, performed at alpha(1)-adrenoceptors of rat liver (alpha 1B) and submaxillary gland (alpha(1A), compound 5 showed an 11-fold selectivity for alpha(1B)-adrenoceptors in contrast to both prazosin and benextramine, which were not selective or selective for the alpha(1A)-subtype respectively.