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Many biologically active complex natural products (e. g. terpenoids, steroids and alkaloids)possess asymmetric quaternary carbon centers. The construction of these asymmetric carbon cen-ters in enantioselective form has been a stimulating subject for organic chemists. Among the methods reported so far, the reaction of construction of nitroolefinic lactones containing asym-metric quaternary carbon centers seems to be promising, because this type of compounds can be
Many biologically active complex natural products (eg terpenoids, steroids and alkaloids) possess asymmetric quaternary carbon centers. The construction of these asymmetric carbon cen-ters in enantioselective form has been a stimulating subject for organic chemists. Among the methods reported so far, the reaction of construction of nitroolefinic lactones containing asym-metric quaternary carbon centers seems to be promising, because this type of compounds can be