| Based on the similar structure of alkyloxy-biphenyl compounds with biological activity, two kinds of new biphenyl compounds containing alkyloxy-biphenyl modified by substituted benzylpiperazine were designed and synthesized by parallel synthesis. Anti-virus activity of some biphenyls was examined. The Ullmann-type coupling reaction to synthesize alkyloxy-biphenyl was carried out in the presence of Ni(PPh3)2Cl/Zn/NaH. Moreover, Chiral 4,4'-dimethoxy-5,6,5',6'-dimethenedioxy-biphenyl were afforded through asymmetric coupling reaction of arylbromide or configuration transform of corresponding compound.The first kind of compounds were synthesized, Based on the lead compound, dimethyl-4,4'-dimethoxy-5,6,5', 6'-dimethenedioxy-biphenyl-2, 2'-dicarbonylate. At first, dimethyl-4, 4'-dimethoxy-5, 6, 5', 6'-dimethenedioxy-biphenyl-2,2'- dicarbony-late were synthesized through coupling reaction of methyl 2-bromo-3,4-methenedi-oxy-5-methoxy-benzene carbonylate in the presence of active copper or coupling agent Ni(PPh3)2Cl/Zn/NaH in good yield, and then it was converted to 4,4' -dimethoxy-5,6,5' ,6' -dimethenedioxy-biphenyl-2-alkyloxycarbonyl-2' -carboxylic acid. The compounds have been further modified by substituted N-benzyl piperazines to afford corresponding novel biphenyls. The structure of these new compounds was confirmed by 1H NMR, IR and ESI-MS.Activity, against simian immunodeficiency virus, of some novel biphenyl compounds, was tested in vitro. All of those showed activity of anti-virus. At the compounds concentration of 7.8 ug/mL, compounds, 2-24, 2-30, 2-42, showed 47.4,38.0, 32.3% reduction in antigen, respectively. Among the three compounds, compound 2-24 possesses the more potent anti-HIV activity. It is noticeable that compound 2-20 exhibit 44.7% reduction in antigen at concentration of 2.0 u.g/mL(2.9uM).The second type of novel compounds, 4,4'-dimethoxy-5,6,5',6'-dimethenedioxy-2-(2-(4-substituted-benzyl~piperazine-l-yl-)-acetoxymethyl)-2'-methoxycarbonyl-biphenyl, were synthesized. The key intermediate, 4,4'-dimethoxy-5,6,5',6'-dimethenedioxyl-2-hydroxymethyl-2'-methoxycarbonyl-biphenyl, was prepared by two methods. One method was selective reduction of methyl-4,4'-dimethoxy-5,6,5', 6'-dimethenedioxy-biphenyl-2,2'-dicarbonylate by NaBH4-I2. The second was intramolecular coupling of 2-bromo-5-methoxy-3,4- methenedioxybenzyl 2-bromo-5-methoxy-3,4-methenedioxybenzoate in the presence of activated copper or CuTC. The structure of the aimed compounds was confirmed by means of 1H NMR, 13C NMR, HSQC, HMBC, NOESY and ESI-MS.(S)-4,4'-dimethoxy-5,6,5',6'-dimethenedioxy-2,2'-di-(4(S)-methyl-oxazoline-l)-biphenyl was synthesized through asymmetric Ullmann coupling reaction or asymmetric Ullmann-type coupling reaction in the presence of Ni(PPh3)2Cl/Zn/NaH.In the thesis, it was found for the first time that the arylbromide with ortho metheneoxy and chiral oxazoline group can couple to give corresponding biphenyl in the presence of Ni(PPh3)2Cl/Zn/NaH. In the asymmetric Ullmann-type, It was noticeable that which was excessive among the biphenyl with S or R configuration was dependent on ratio of Ni(PPh3)2Cl2 to aryl bromide. 0.5 equiv Ni(PPh3)2Cl2 gaveexcessive R and 1 equiv or more Ni(PPh3)2Cl2 afforded excessive S. The different stereoselectivity should reflect two kinds of coupling mechanism, intermolecular and intramolecular coupling of Ni-complex intermediate.we have also found another efficacious method to prepare (S)-4,4'-dimethoxy-5,6,5',6'-dimethenedioxy-2,2'-di-[4(S)-methyl-oxazoline-l]-biph enyl through configuration transform of (R/S)-4,4'-dimethoxy-5,6,5',6'-dimethenedioxy-2,2'-di-(4(S)-methyl-oxazoline-l)-bi-biphenyl in excellent yield promoted by interaction between chiral oxazolines moiety of biphenyl and Cu(I). (S)-dimethyl-4,4'-dimethoxy-5,6,5',6'-dimethenedioxy-biphen-yl-2,2'-dicarboxylate was prepared from (S)-2,2'-dioxazoline biphenyl isomer conveniently.At last, the mechanism of asymmetric Ullmann coupling, asymmetric Ullmann-t...
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