PubMed Health⌕ Search
Home/Archive/PubMed

PubMed · 34040

Synthesis and preliminary biological studies of 4- and 5-[2-hydroxy-3-(isopropylamino)propoxy]benzimidazoles: selective beta2 adrenergic blocking agents.

C R Crooks·J Wright·P S Callery·J E Moreton
View original source ↗Export metadata ↓

Abstract

Benzimidazoles carrying the 2-hydroxy-3-(isopropylamino)propoxy side chain at either the C-4 or C-5 ring positions were synthesized and investigated for beta-adrenergic blocking activity. Both compounds demonstrated beta2 selectivity when evaluated in guinea pig atrial and tracheal preparations. The C-4 isomer was 17 times more selective toward tracheal tissue, and its overall potency was roughly comparable to that of propranolol. beta2 selectivity of the C-5 isomer was minimal, with a potency about one-hundredth that of propranolol.

Explore related subjects

Adrenergic beta-AntagonistsAirway ResistanceAnimalsBenzimidazolesGuinea PigsHeart RateIn Vitro TechniquesMethodsMyocardial ContractionJournal Article

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

C R Crooks, J Wright, P S Callery, J E Moreton. 1979. Synthesis and preliminary biological studies of 4- and 5-[2-hydroxy-3-(isopropylamino)propoxy]benzimidazoles: selective beta2 adrenergic blocking agents.. https://doi.org/10.1021/jm00188a019

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed1979

[The influence of a beta-adrenolytic premedication on cardiovascular parameters and plasma free fatty acids during esophago-gastro-duodenoscopy (author's transl)].

Three groups of patients with different premedications were examined for changes of blood pressure, heart rate, ECG and plasma free fatty acid levels during esophago-gastro-duodenoscopy: Group A was premedicated with Bunitrolol, group B was premedicated with Hyoscin-N-butyl-bromide and diazepam, group C was endoscopied without premedication. The pulse rate rose significantly less in group A than in groups A and C; the same phenomenon was observed with regard to the systolic blood pressure. Premature beats occurred in all 3 groups: 32 per cent of the patients in group A, 43 per cent in group B and 60 per cent in group C had at least occasional premature beats; an accumulation of premature beats however occurred significantly less frequently in group A than in groups B or C. A drop of the ST-part of the ECG occurred with about the same frequency in each group. An increase of the plasma free fatty acids, which was noted in groups B and C, could be observed in Group A. A pre-endoscopic medication of beta blocking agents could be a useful measure in patients with labile arterial hypertension, vegatative dysregulation and a hyperkinetic heart syndrome.

Adrenergic beta-Antagonists↗
PubMed1979

Antihypertensive and cardiac effects of two novel beta-adrenoceptor blocking drugs.

Two new beta-adrenoceptor blocking drugs with acute antihypertensive and positive inotropic effects are described: Compound A (2-[4-(3-tert.butylamino-2-hydroxypropoxy)phenyl]-4-trifluoromethylimidazole) and MK-761 (2-(3-tert.butylamine-2-hydroxypropoxy)-3-cyanopyridine hydrochloride). In SH rats both compounds, given orally, lowered arterial pressure and were more potent than hydralazine. The antihypertensive effect of compound A but not of MK-761 was antagonized by timolol. Both compounds had positive inotropic activity on cat heart papillary muscles; these effects were antagonized by timolol. The pretreatment of animals with reserpine greatly reduced the positive inotropic effect of MK-761 but not of compound A. The acute antihypertensive and positive inotropic effects of compound A are like to be at least partially due to stimulation of beta-adrenoceptors, e.g. intrinsic sympathomimetic activity. The effects of MK-761 on the same parameters appear to be mediated by different mechanisms.

Adrenergic beta-Antagonists↗