Design, Synthesis, and Structure−Activity Relationship Studies of 3,4,6-Triphenylpyran-2-ones as Selective Cyclooxygenase-2 Inhibitors
摘要:
A group of regioisomeric 3,4,6-triphenylpyran-2-ones with a MeSO2 pharmacophore at the paraposition of either a C-3 phenyl or a C-4 phenyl substituent on the central six-membered pyran-2-one ring were prepared and evaluated in vitro for their abilities to inhibit the isozymes COX-1 and COX-2. Structure-activity relationship (SAR) data, acquired by substituent modification at the para-position of the C-6 phenyl ring attached to the central pyranone, showed that 6-(4-methoxyphenyl)-3-(4-methanesulfonylphenyl)-4-phenylpyran-2-one (12e) was the most potent and selective COX-2 inhibitor (COX-2 IC50 = 0.02 muM; COX-1 IC50 > 100 muM) with a high COX-2 selectivity index (SI > 5000) relative to the reference drugs celecoxib (COX-2 IC50 = 0.07 muM; SI = 474) and rofecoxib (COX-2 IC50 = 0.50 muM; SI > 200). 6-(4-Methoxyphenyl)-3-(4-methanesulfonylphenyl)-4-phenylpyran-2-one (12e) was a more potent oral antiinflammatory agent (ID50 = 5.6 mg/kg) than celecoxib (ID50 = 10.8 mg/kg) in a carrageenan-induced rat paw edema assay. In a 4% NaCl-induced abdominal constriction assay, a 5 mg/kg oral dose of 12e exhibited good analgesic activity at different time intervals producing 37.5 and 69% inhibition of writhing at 30 and 60 min, respectively. In contrast, the corresponding 6-(4-methoxyphenyl)-4-(4-methanesulfonylphenyl)-3-phenylpyran-2-one regiosiomer (12o) was a less potent and selective COX-2 inhibitor (COX-2 IC50 = 0.45 muM; SI = 70). A molecular modeling study for 12e indicated that the p-OMe substituent on the C-6 phenyl ring interacts with the COX-2 binding site amino acids Ile(345), Val(349), Leu(359), Leu(531), and Met(535) and that the OMe substituent may be responsible for proper orientation of the C-3 p-SO2Me-phenyl ring within the COX-2 secondary pocket (Gln(192), Arg(513), and Phe(518)). These results show that the COX-2 selectivity and potency of 3,4,6-triphenylpyranone regioisomers can be modulated by appropriate placement of the p-SO2Me pharmacophore on either the C-3 or C-4 phenyl moiety. In addition, electronic properties at the para-position of a C-6 phenyl substituent on the central pyranone ring govern COX-2 inhibitory potency and selectivity by controlling the orientation of the p-SO2Me pharmacophore within the COX-2 secondary pocket.
Copper-Catalyzed Direct Coupling of Unprotected Propargylic Alcohols with P(O)H Compounds: Access to Allenylphosphoryl Compounds under Ligand- and Base-Free Conditions
The first facile and efficient copper-catalyzeddirect C–P cross-coupling of unprotected propargylic alcohols with P(O)H compounds has been developed, providing a general, one-step approach to construct valuable allenylphosphoryl frameworks with operational simplicity and high step- and atom-economy under ligand-, base-, and additive-free conditions.
The enantioselective catalytic alkynylation of aromatic aldehydes is reported using a sterically highly hindered bis-cyclometalated rhodium-based Lewis acid catalyst featuring the octahedral metal as the only stereogenic center. Yields of 58–98% with 79–98% enantiomeric excess were achieved using 1–2 mol % of catalyst. This work complements previous work from our laboratory on the enantioselective alkynylation
group-substituted carbonyl compounds. A palladium-catalyzed aminocarbonylation of propargyl acetates with amines for the synthesized tri-/tetrasubstituted 2,3-allenamides has been developed. A broad range of tri-/tetrasubstituted 2,3-allenamides have been prepared from propargyl acetates in good to excellent yields. The reaction featured mild reaction conditions and good functional group tolerance. The
Synthesis and biological evaluation of 3-amino-2-pyrones as selective cyclooxygenase-1 (COX-1) inhibitors
作者:Xue-Ping Chu、Qing-Fa Zhou、Shen Zhao、Fei-Fei Ge、Mian Fu、Jia-Peng Chen、Tao Lu
DOI:10.1016/j.cclet.2013.01.005
日期:2013.2
A group of 3-amino-2-pyrones were synthesized and their biological activities were evaluated for inhibiting cyclooxygenase (COX) activity. This study has led to the identification of COX-1-selective inhibitors. Among the tested compounds, the compound 5j exhibited the most potent COX-1 inhibitory activity (IC50 = 19.32 mu g/mL) and COX-1 selectivity index (SI = 41.98). (C) 2013 Qing-Fa Zhou. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.