Synthesis and antihypertensive activity of some thienylethanolamines

Abstract

Synthesis of a series of thienylethanolamines having varying substituents on the thiophene ring and on the nitrogen atom is described using the general procedure reported earlier. In the determination of their pharmacological profile, some of the derivatives showed marked antihypertensive activity in the spontaneously hypertensive rat model. Tests are also reported which demonstrated that some of these derivatives antagonized alpha- and/or beta-adrenoreceptor activities. The ability of this class of compounds to inhibit catecholamine-induced release of free fatty acids by adipose tissue was demonstrated. Structure-activity relationships in different tests were also determined.

Substrate‐Controlled Diastereoselectivity Switch in the Formation of Dihydrothieno[3,4‐c]coumarins via [4+1] Annulations

“…The scope was substantial, and high yields were generally obtained for substrates having various substitutions. Only transproducts were observed in the [4 + 1] annulations (> 99:1 dr, entries [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17]. It appeared that the substitution patterns, regardless of the positions or electronic natures on the aromatic ring (R 1 , R 2 or Ar), had little effect on the reaction.…”

“…[9][10] Among heteroaromatic compounds, thiophenes are unique sulfur-containing heterocycles that attract particular attention due to their special role as building blocks in natural products, pharmaceutical agents and materials. [11][12][13][14][15][16] Therefore, a variety of excellent protocols have been devoted to obtaining these valuable heterocycles, which include reactions between 1, 4-dithiane-2,5-diol and electron-deficient olefins (e. g., unsaturated aldehydes, [17a] trans-b-nitrostyrenes [17b] or chalcones [18] ) and domino reactions of other thiols to active alkenes. [19] Additionally, coumarins are important heterocyclic frameworks that are widely present in natural products and exhibit a broad range of biological and therapeutic activities; they have been the subject of intensive research.…”

The First Gold‐Catalyzed CS Bond Formation: Cycloisomerization of α‐Thioallenes to 2,5‐Dihydrothiophenes

“…For example, oxidation or reduction of the resulting heterocycles smoothly affords thiophenes or tetrahydrothiophenes which are important structural motifs in natural products and biologically active compounds (Scheme ). These include antihypertensive compounds,6 potential inhibitors of HIV,7 glucosidase inhibitors (salacinol, kotalanol),8 an essential coenzyme (biotin)9 and a cholecystokinin type‐B receptor antagonist (tetronothiodin) 10. Moreover, 2,5‐disubstituted tetrahydrothiophenes can be utilized as chiral ligands in enantioselective reactions 11…”

Thiophene Isosters of Phenylethanolamines

“…The formation of the by-products was rationalized as resulting from the pseudoaromatic character of the thiophene nucleus. The ethanolamines described in this paper were evaluated for their biological activity in the cardiovascular field (6).…”