Synthesis and 5-HT2A antagonist activity of derivatives of the novel heterocycles indolo[3,2-d]pyrrolo[3,2-g]azecine and benzo[d]pyrrolo[3,2-g]azecine compared to the benz[d]indolo[2,3-g]azecine derivative LE 300.
An indolo[3,2-d]pyrrolo[3,2-g]azecine and a benzo[d]pyrrolo[3,2-g]azecine analogue of the potent dopamine receptor antagonist LE 300 (7-methyl-6,7,8,9,14,15-hexahydro-5H-benz[d]indolo[2,3-g]azecine) have been prepared in multi-step reactions via C-N bond cleavage of corresponding quaternary N-methylquinolizinium iodides. LE 300, the target compounds and two precursor quinolizines have been tested in vitro for antagonist activity at 5-HT2A receptors (rat tail artery) and H1 receptors (guinea-pig ileum), respectively. LE 300 and compound 19 (3,6-dimethyl-4,5,6,7,8,13-hexahydro-3H-benzo[d]pyrrolo[3,2-g]azecine) competitively inhibited 5-HT-induced contractions with similar nanomolar potency (pA2 = 8.32 and 8.01, respectively) but were less active than the reference antagonist ketanserin (pA2 = 9.55). Compound 19 displayed moderate H1-antihistaminic activity in the guinea-pig ileum assay (pA2 = 7.37).
Rostom
S A
SA
Department of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Alexandria, Alexandria, A.R., Egypt.
Farghaly
A M
AM
Soliman
F S
FS
el-Semary
M M
MM
Elz
S
S
Lehmann
J
J
D000818:Animals; D001667:Binding, Competitive / Q000187:drug effects; D006168:Guinea Pigs; D066298:In Vitro Techniques; D007211:Indoles / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects; D011758:Pyrroles / Q000138:chemical synthesis* / Q000494:pharmacology*; D051381:Rats; D044402:Receptor, Serotonin, 5-HT2A; D011985:Receptors, Serotonin / Q000187:drug effects*; D012702:Serotonin Antagonists / Q000138:chemical synthesis* / Q000494:pharmacology*
C409874:7-methyl-6,7,8,9,14,15-hexahydro-5H-benz(d)indolo(2,3-g)azecine; D007211:Indoles; D011758:Pyrroles; D044402:Receptor, Serotonin, 5-HT2A; D011985:Receptors, Serotonin; D012702:Serotonin Antagonists; C434770:benzo(d)pyrrolo(3,2-g)azecine; C434771:indolo(3,2-d)pyrrolo(3,2-g)azecine