Drug metabolism-based design, synthesis, and bioactivities of 1-(2,6-dimethylphenoxy)-2-(3,4-dimethoxyphenylethylamino)propane hydrochloride (DDPH) analogs as α1-adrenoceptors antagonists.

1-(2,6-dimethylphenoxy)-2-(3,4-dimethoxyphenylethylamino)propane hydrochloride (DDPH) is a potent α1-adrenoceptor antagonist that is currently under Phase II clinic trials. However, the fast metabolism has restricted its further use. In this paper, 11 DDPH analogs were designed according to the probable metabolism pathways of DDPH, and featured the structures of halogen, methyl, and cyano groups at the 3-, or 4-position of aromatic ring A to block the hydroxylation, and one hydroxyl group at the 3-, or 4-position of aromatic ring B to extend the duration time. These compounds were synthesized in moderate to good yields from the reductive amination of substituted phenoxyacetones with substituted phenylethylamines, and fully characterized with ¹H NMR, IR, and HRMS. Biological evaluation indicated that most of the compounds exhibited strong blocking and moderate to good antihypertensive activities. It is clear that the compounds having 4-OH/3-OMe on group B exhibited higher blocking activities and longer duration time than their corresponding analogs having 4-OMe/3-OMe (and also 3-OH/4-OMe). Among them, compound 13 having bromo group at the 4-position of ring A and 4-OH/3-OMe on group B, exhibited the highest blocking activity, whereas compound 17 that had a methyl group at the 4-position of ring A and a hydroxyl group at the 4-position of ring B, was more active than potent DDPH in terms of both blocking and antihypertensive activities. In addition, the possible correlations between the blocking and antihypertensive activities are also briefly discussed.

Synthesis and blocking activities of isoindolinone- and isobenzofuranone-containing phenoxylalkylamines as potent α(1)-adrenoceptor antagonists.

This paper describes the synthesis and blocking activities of twelve new isoindolinone- and isobenzofuranone-containing phenoxylalkylamines as potent α(1)-Adrenoceptor antagonists. These compounds were synthesized in moderate to good yields starting from 3,4-dimethylphenol, and characterized with (1)H-NMR, MS, IR and elemental analysis. Their blocking activities toward α(1)-Adrenoceptors were evaluated on isolated rat anococcygeus muscles. The results indicated that these compounds were very strong in blocking α(1)-Adrenoceptors, and most of them exhibited activities that were comparable to that of known potent α(1)-Adrenoceptor antagonist 1-(2,6-dimethylphenoxy)-2-(3,4-dimethoxyphenylethylamino)propane hydrochloride (DDPH).

Synthesis and blocking activities of a new class of α1-adrenoceptor antagonists.

Finding effective chemotherapeutic agents for clinical use is a long-lasting goal in medicinal chemistry. In this study, we report a new class of α1-adrenoceptor (α1-AR) antagonists. Specifically, we describe the synthesis and the blocking activities toward α1-AR of 7-(2-hydroxypropoxy)-3,4-dihydroisoquinolin-1(2H)-one 1 and its structurally perturbed analogs 2-11 that were designed according to the principle of bioisosterism. Their structures were identified with IR, (1) H NMR, MS, HRMS and elemental analysis. The blocking activities of compounds 1-11 were evaluated on isolated rat anococcygeus muscles. The results indicated that these compounds showed moderate to good activities. Among them, compound 1 exhibited the highest activity that was comparable to those of known α1-AR antagonists tamsulosin and DDPH (1-(2,6-dimethylphenoxy)-2-(3,4-di- methoxyphenylethylamino)propane hydrochloride) and thus may be exploitable as a lead compound for the discovery of promising α1-AR antagonists.

[Synthesis and anti alpha-adrenoceptor activity in vitro of 4-((4-((2-substitutedphenoxy)ethyl)-1-piperazinyl) methyl)- 1,2-dihydro-quinoline-2-one compounds].

AIM: To study the synthesis and anti alpha-adrenoceptor activity of 1,2-dihydro-quinoline-2-one compounds. METHODS: Acylation, bromination and cyclization, and substitute reactions were used in the synthesis of the title compounds IV. A proposed mechanism was showed to explain the unusual compounds 5 and 6 in the route C. The inhibition activity of the six target compounds were tested. RESULTS: Twelve new compounds were synthesized (II1-6 and IV1-6). Among them, six new compounds (IV1-6) are the title compounds. Structure of the title compounds were determined by IR, 1HNMR, MS and HRMS. CONCLUSION: Compounds IV3, IV4 and IV6 showed inhibitiion activity, and were worth further studying.