L-765314

• CAT Number: I007591
• CAS Number: 189349-50-6
• Molecular Formula: C27H34N6O5
• Molecular Weight: 522.60
• Purity: ≥95%
• Synonyms: benzyl (2S)-4-(4-amino-6,7-dimethoxyquinazolin-2-yl)-2-(tert-butylcarbamoyl)piperazine-1-carboxylate
• InChI: InChI=1S/C27H34N6O5/c1-27(2,3)31-24(34)20-15-32(11-12-33(20)26(35)38-16-17-9-7-6-8-10-17)25-29-19-14-22(37-5)21(36-4)13-18(19)23(28)30-25/h6-10,13-14,20H,11-12,15-16H2,1-5H3,(H,31,34)(H2,28,29,30)/t20-/m0/s1
• InChIKey: CGWOIDCAGBKOQL-FQEVSTJZSA-N
• SMILES: CC(C)(C)NC(=O)C1CN(CCN1C(=O)OCC2=CC=CC=C2)C3=NC4=CC(=C(C=C4C(=N3)N)OC)OC

L-765314 is a potent and selective α1b adrenergic receptor antagonist with Kis of 5.4 nM and 2.0 nM for rat and human α1b adrenergic receptor, respectively.
L-765314 exhibits two displacement sites. The high-affinity site accounts for approximately 25% of binding (IC50) 1.90 nM and represents binding to the R1b sites. The low-affinity site accounts for the residual 75% of binding (IC50) 790 nM and represents binding to the R1a sites[1].
The results of plasma assayed by liquid chromatograph/mass spectrometer (LCMS) show that the mean Cmax of L-765314 (A322312) is 1.05 μM and the t1/2 is 0.5 h. L-765314 shows weak potency for inhibiting the pressor response to either phenylephrine or A-61603 (AD25>3 mg/kg for each). On the basis of the inhibition of pressor responses to the R1a subtype selective agonist A-61603, L-765314 appears to be selective versus the R1a receptor up to a dose of 0.3 mg/kg. The results of hypotensive potency in rats show that both L-765314 and terazosin tend to decrease heart rate (about 25 bpm at 1 mg/kg iv)[1].

Reference

[1]. Patane MA, et al. 4-Amino-2-[4-[1-(benzyloxycarbonyl)-2(S)- [[(1,1-dimethylethyl)amino]carbonyl]-piperazinyl]-6, 7-dimethoxyquinazoline (L-765,314): a potent and selective alpha1b adrenergic receptor antagonist. J Med Chem. 1998 Apr 9;41(8):1205-8.
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[2]. Tobias Böhmer, et al. The α1B-adrenoceptor subtype mediates adrenergic vasoconstriction in mouse retinal arterioles with damaged endothelium. Br J Pharmacol. 2014 Aug; 171(16): 3858–3867.
 [Content Brief]