CP-105696

• CAT Number: I006196
• CAS Number: 158081-99-3
• Molecular Formula: C28H28O4
• Molecular Weight: 428.52
• Purity: ≥95%
• Synonyms: 1-[(3S,4R)-4-hydroxy-3-[(4-phenylphenyl)methyl]-3,4-dihydro-2H-chromen-7-yl]cyclopentane-1-carboxylic acid
• InChI: InChI=1S/C28H28O4/c29-26-22(16-19-8-10-21(11-9-19)20-6-2-1-3-7-20)18-32-25-17-23(12-13-24(25)26)28(27(30)31)14-4-5-15-28/h1-3,6-13,17,22,26,29H,4-5,14-16,18H2,(H,30,31)/t22-,26+/m0/s1
• InChIKey: KMNLXCBYBKHKSK-BKMJKUGQSA-N
• SMILES: C1CCC(C1)(C2=CC3=C(C=C2)C(C(CO3)CC4=CC=C(C=C4)C5=CC=CC=C5)O)C(=O)O

CP-105696 is a potent and selective Leukotriene B4 Receptor antagonist, with an IC50 of 8.42 nM.
CP-105696 is a structurally novel, selective and potent LTB4 receptor antagonist. In vitro, CP-105696 inhibits [3H]LTB4 (0.3 nM) binding to high-affinity LTB4 receptors on human neutrophils with an lC50 value of 8.42±0.26 nM. Scatchard analyses of [3H]LTB4 binding to these high-affinity receptors indicate that CP-105696 acts as a noncompetitive antagonist. CP-105696 inhibits human neutrophil chemotaxis mediated by LTB4 (5 nM) in a noncompetitive manner with an IC50 value of 5.0±2.0 nM. Scatchard analyses of [3H]LTB4 binding to low-affinity receptors on neutrophils indicate that CP-105696 acts as a competitive antagonist at this receptor, and inhibition of LTB4-mediated CD11b upregulation on human neutrophils is competitively inhibited by CP-105696 (pA2=8.03±0.19). CP-105696 at 10 μM does not inhibit either human neutrophil chemotaxis or CD11b upregulation mediated through alternate (i.e., C5a, lL-8, PAF) G-protein coupled chemotactic factor receptors. In isolated human monocytes, LTB4 (5 nM)-mediated Ca2+ mobilization is inhibited by CP-105696 with an lC50 value of 940±70 nM[1].
At a dose of 50 mg/kg/day (28 days), B10.BR (H2k) allografts transplanted into C57Bl/6 (H2b) recipients are significantly protected, as reflected by the mean survival time versus control grafts (27±20 days [n=10] vs. 12±6 days [n=14]; P=0.0146). Using an induction protocol (day -1 to day 3), CP-105696 at 100 mg/kg/day significantly prolongs allograft survival (33±23 days [n=9]; P=0.0026), but CP-105696 at 10 mg/kg/day does not (18±16 days [n=8]; P=0.1433). Syngeneic grafts survive indefinitely (n=11). Immunohistological evaluation of allografts at rejection reveals a mononuclear cell infiltrate composed primarily of CD3+ and CD11b+ (Mac-1+) cells, which are infrequent in syngeneic grafts. Allografts from mice treated with CP-105696 at 50 or 100 mg/kg/day demonstrat a selective reduction in β2-integrin (Mac-1) expression on monocytes/macrophages, as demonstrated by CD11b staining density compared with allograft controls[2].

Reference

[1]. Showell HJ, et al. The in vitro and in vivo pharmacologic activity of the potent and selective leukotriene B4 receptor antagonist CP-105696. J Pharmacol Exp Ther. 1995 Apr;273(1):176-84.
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[2]. Weringer EJ, et al. Antagonizing leukotriene B4 receptors delays cardiac allograft rejection in mice. Transplantation. 1999 Mar 27;67(6):808-15.
 [Content Brief]