| Bioactivity | BIBS 39 is a new nonpeptide angiotensin II (AII) receptor antagonist.Target: Angiotensin Receptorin vitro: BIBS 39 displaces [125I] AII from its specific binding sites with a Ki value of 29 ± 7 nM for the AII subtype 1 (AT1) receptor and a Ki value of 480 ± 110 nM for the AII subtype 2 (AT2) receptor. BIBS 222 shows a Ki value of 20 ± 7 nM for the AT1 subtype and a Ki value of 730 ± 170 nM for the AT2 subtype. BIBS 39 is 17 times more selective for the AT1 subtype and BIBS 222 37 times. BIBS 39 shifts the AII concentration-contractile response curves in isolated rabbit aorta to the right in a parallel fashion. [1]in vivo: In pithed rats, BIBS 39 dependently shifts the dose-response curve of AII to the right without affecting the maximal response. BIBS 222 also causes parallel shifts to the right but a significant reduction of the maximal responses was observed at 3 and 10 mg/kg i.v. These results show that the benzimidazole derivatives BIBS 39 is a potent and selective AII receptor antagonists. Substitution with a benzimidazole moiety results into a considerable loss of selectivity for the AT1 receptor subtype compared with an imidazole moiety as, for instance, in DuP 753.[1] BIBS 39 is a new nonpeptide angiotensin receptor blockers that has affinity for both AT1- and AT2-receptors, is also a potent antagonist of the cardiovascular effects of AII in pithed rabbits. [2] | ||||||||||||
| Name | BIBS 39 | ||||||||||||
| CAS | 133085-33-3 | ||||||||||||
| Formula | C32H36N4O3 | ||||||||||||
| Molar Mass | 524.65 | ||||||||||||
| Appearance | Solid | ||||||||||||
| Transport | Room temperature in continental US; may vary elsewhere. | ||||||||||||
| Storage |
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| Reference | [1]. Zhang J, et al. Characterization of BIBS 39 and BIBS 222: two new nonpeptide angiotensin II receptor antagonists. Eur J Pharmacol. 1992 Jul 21;218(1):35-41. [2]. Zhang J, et al. Hemodynamic effects of angiotensin II and the influence of angiotensin receptor antagonists in pithed rabbits. J Cardiovasc Pharmacol. 1995 May;25(5):724-31. |