The synthesis of kermesic acid and isokermesic acid derivatives and of related dihydroxyanthraquinones
The synthesis of kermesic acid and isokermesic acid derivatives and of related dihydroxyanthraquinones
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胭脂酸和异胭脂酸衍生物及相关二羟基蒽醌的合成
DOI：
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发表时间：
1997
期刊：
影响因子：
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通讯作者：
J. Tyman
中科院分区：
文献类型：
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作者：
S. Bingham;J. Tyman
以2-溴代马来酸酐和3-烷氧羰基-2，4-双（三甲基硅氧基）戊-1，3-二烯为原料，经一步Diels-Alder反应合成了Cochinellic酸酐甲酯、乙酯和苄酯（4-甲氧基-4-乙氧基-和4-苄氧羰基-5-羟基-3-甲基邻苯二甲酸酐）。相应的5-甲基醚乙酯通过类似的加成反应得到，但用3-乙氧羰基-2-甲氧基-4-三甲基甲硅烷基氧基戊-1，3-二烯。在三氟化硼-乙醚存在下，1，4-二甲氧基苯与胭脂虫酸酐甲酯发生酰化反应合成6-脱氧胭脂虫酸甲酯，但没有成功。优选的途径是通过3-烷氧羰基-2，4-双（三甲基甲硅烷基氧基）戊-1，3-二烯与萘茜（或2-氯萘茜）的狄尔斯-阿尔德加成。6-脱氧胭脂红酸甲酯的四乙酸铅氧化得到双（醌），其Thiele乙酰氧基化在水解和全甲基化后得到相等比例的胭脂红酸和异胭脂红酸的衍生物的混合物。3-氯胡桃醌和3-烷氧羰基-2，4-双（三甲基甲硅烷基氧基）戊-1，3-二烯的Diels-Alder加成导致芦荟皂苷-I（3，8-二羟基-2-甲氧羰基-1-甲基蒽-9，10-醌）的合成得到改进，而胡桃醌本身提供可能是3，5-二羟基化合物的异构体。
Cochinellic anhydride methyl, ethyl and benzyl esters (4-methoxy-4-ethoxy- and 4-benzyloxy-carbonyl-5-hydroxy-3-methylphthalic anhydrides) have been prepared by a single stage Diels–Alder reaction of 2-bromomaleic anhydride with 3-alkoxycarbonyl-2,4-bis(trimethylsilyloxy)penta-1,3-dienes. The corresponding 5-methyl ether ethyl ester has been obtained by a similar addition reaction but with 3-ethoxycarbonyl-2-methoxy-4-trimethylsilyloxypenta-1,3-diene. The synthesis of methyl 6-deoxykermesate by the acylation of 1,4-dimethoxybenzene in the presence of boron trifluoride–diethyl ether with cochinellic anhydride methyl ester is unsuccessful. The preferred route is by the Diels–Alder addition of 3-alkoxycarbonyl-2,4-bis(trimethylsilyloxy)penta-1,3-dienes to naphthazarin (or 2-chloronaphthazarin). Lead tetraacetate oxidation of methyl 6-deoxykermesate affords a bis(quinone), Thiele acetoxylation of which gives after hydrolysis and permethylation, a mixture of derivatives of kermesic and isokermesic acids in equal proportions. The Diels–Alder addition of 3-chlorojuglone and 3-alkoxycarbonyl-2,4-bis(trimethylsilyloxy)penta-1,3-dienes has led to an improved synthesis of aloesaponarin-I (3,8-dihydroxy-2-methoxycarbonyl-1-methylanthra-9,10-quinone), while juglone itself affords an isomer which may be the 3,5-dihydroxy compound.