合成路线:The condensation of 2-bromo-4,5-diethoxybenzaldehyde dimethyl ketal (I) with pyridine-4-carbaldehyde (II) by means of NaH in THF gives the expected addition product (III),which by treatment with acetic acid in refluxing toluene yields the isobenzofuran (IV) (unstable,not isolated compound) that is submitted immediately to a Diels-Alder cyclization with dimethyl maleate (V) to afford the epoxy-tetrahydronaphthalene (VI).The aromatization of (VI) with trifluoroacetic acid (TFA) in chloroform,or with BF3/ethyl ether in acetonitrile gives 6,7-diethoxy-1-(4-pyridyl)naphthalene-2,3-dicarboxylic acid dimethyl ester (VII).The oxidation of (VII) with m-chloroperbenzoic acid (MCPBA) in dichloromethane gives the corresponding N-oxide (VIII),which is isomerized to the pyridone (IX) by refluxing in acetic anhydride.The condensation of (IX) with 2-chloroethyl methyl ether (X) by means of NaH or Li in DMF affords the N-substituted pyridone (XI),which is finally reduced with NaBH4 in THF.
参考文献标题:Antiasthma agent
文献作者:Iwasaki,T.; Kondo,K.; Ikesawa,I.; Yoshikawa,H.; Yamashina,S.(Tanabe Seiyaku Co.,Ltd.)
参考来源:JP 1995101861
合成路线:The condensation of 2-bromo-4,5-diethoxybenzaldehyde dimethyl ketal (I) with pyridine-4-carbaldehyde (II) by means of NaH in THF gives the expected addition product (III),which by treatment with acetic acid in refluxing toluene yields the isobenzofuran (IV) (unstable,not isolated compound) that is submitted immediately to a Diels-Alder cyclization with dimethyl maleate (V) to afford the epoxy-tetrahydronaphthalene (VI).The aromatization of (VI) with trifluoroacetic acid (TFA) in chloroform,or with BF3/ethyl ether in acetonitrile gives 6,7-diethoxy-1-(4-pyridyl)naphthalene-2,3-dicarboxylic acid dimethyl ester (VII).The oxidation of (VII) with m-chloroperbenzoic acid (MCPBA) in dichloromethane gives the corresponding N-oxide (VIII),which is isomerized to the pyridone (IX) by refluxing in acetic anhydride.The condensation of (IX) with 2-chloroethyl methyl ether (X) by means of NaH or Li in DMF affords the N-substituted pyridone (XI),which is finally reduced with NaBH4 in THF.
参考文献标题:Novel selective PDE IV inhibitors as antiasthmatic agents.Synthesis and biological activities of a series of 1-aryl-2,3-bis(hydroxymethyl)naphthalene lignans
文献作者:Iwasaki,T.; Kondo,K.; Kuroda,T.; Moritani,Y.; Yamagata,S.; Sugiura,M.; Kikkawa,H.; Kaminuma,O.; Ikezawa,K.
参考来源:J Med Chem 1996,39(14),2696-704
合成路线:The condensation of 2-bromo-4,5-diethoxybenzaldehyde dimethyl ketal (I) with pyridine-4-carbaldehyde (II) by means of NaH in THF gives the expected addition product (III),which by treatment with acetic acid in refluxing toluene yields the isobenzofuran (IV) (unstable,not isolated compound) that is submitted immediately to a Diels-Alder cyclization with dimethyl maleate (V) to afford the epoxy-tetrahydronaphthalene (VI).The aromatization of (VI) with trifluoroacetic acid (TFA) in chloroform,or with BF3/ethyl ether in acetonitrile gives 6,7-diethoxy-1-(4-pyridyl)naphthalene-2,3-dicarboxylic acid dimethyl ester (VII).The oxidation of (VII) with m-chloroperbenzoic acid (MCPBA) in dichloromethane gives the corresponding N-oxide (VIII),which is isomerized to the pyridone (IX) by refluxing in acetic anhydride.The condensation of (IX) with 2-chloroethyl methyl ether (X) by means of NaH or Li in DMF affords the N-substituted pyridone (XI),which is finally reduced with NaBH4 in THF.
参考文献标题:T-440
文献作者:Graul,A.; Leeson,P.; Castar,J.
参考来源:Drugs Fut 1997,22(7),729
合成路线:An efficient N-alkylation process suitable for the large-scale synthesis of T-440 has been reported: Alkylation of the previously reported pyridone (I) with 2-methoxyethyl iodide (II) by means of LiH in hot DMF gives the N-alkylated pyridone (II) purified by crystallization.Finally,this compound is reduced with NaBH4 and MeOH in refluxing THF.
参考文献标题:An efficient synthesis of the anti-asthmatic agent T-440: A selective N-alkylation of 2-pyridone
文献作者:Sugahara,M.; Moritani,Y.; Kuroda,T.; Kondo,K.; Shimadzu,H.; Ukita,T.
参考来源:Chem Pharm Bull 2000,48(4),589
产品链接: CAS No. 155043-84-8››