Polycyclic hydroxy quinones. 28. Synthesis and Diels-Alder reactions of N,N,O-triacyl derivatives of 10-amino-9-hydroxy-1,4-anthraquinones. An efficient, regiospecific synthesis of (.+-.)-5-iminodaunomycinone, (.+-.)-4-demethoxy-5-iminodaunomycinone, and (.+-.)-daunomycinone
摘要:
The development of a general strategy for the construction of anthracyclinones based on a Diels-Alder reaction of substituted derivatives of 10-amino-9-hydroxy-1,4-anthraquinone is described. The key stages are (i) formation of N,O,O-triacyl derivatives of 1,4-dihydroxy-9,10-anthraquinone monoimines in a tautomer specific fashion, (ii) transacylation into N,N,O-triacyl derivatives of the corresponding 10-amino-9-hydroxy-1,4-anthraquinone, and (iii) Diels-Alder reaction with an appropriately substituted 1,3-diene regiocontrolled by steric factors. This strategy has been applied to the total synthesis of (+/-)-5-iminodaunomycinone (4) and (+/-)-4-demethoxy-5-iminodaunomycinone (3) and to a novel and short synthesis of (+/-)-daunomycinone (5).
Synthesis of Erythrina and related alkaloids. XVI Diels-Alder approach : Total synthesis of dl-erysotrine, dl-erythraline, dl-erysotramidine, dl-8-oxoerythraline and their 3-epimers.
Total synthesis of erythrinan alkaloids was achieved by a strategy based on the Diels-Alder reaction of activated butadienes to a dioxopyrroline. The reaction of isoquinolinopyrrolinedione (15) with 1, 3-bis-O-substituted butadienes proceeded in a regiospecific and stereoselective manner to give erythrinan derivatives (20) and (21). Lithium borohydride reduction of the adduct (20) or (21), followed by acid hydrolysis afforded the enone (33). Mesylation of 33 and subsequent demethoxycarbonylation of 42 under neutral conditions gave the dienone (43). Meerwein-Ponndorf reduction of 43 and subsequent methylation afforded erysotramidine (2a) and 8-oxoerythraline (2b). Aluminum hydride reduction of the 8-oxo derivatives (2) furnished dl-erysotrine (1a) and dl-erythraline (1b).
An efficient, regiospecific synthesis of (±)-Daunomycinone
作者:T. Ross Kelly、Lakshminarayanan Ananthasubramanian、Kripinath Borah、John W. Gillard、Richard N. Goerner、Patrick F. King、Judith M. Lyding、Wen-Ghih Tsang、Jacob Vaya
DOI:10.1016/s0040-4020(01)91516-9
日期:1984.1
ofregiochemistry in the Diels-Alder reactions of substituted naphthazarins is described. Application of this strategy to the synthesis of(±)-daunomycinone (2) employs two successive regiochemically controlled Diels-Alder reactions and leads to a ten-step, regiospecificsynthesis of(±)-2 in 36% overall yield (Scheme 4).
Total syntheses of two homerythrinan alkaloids, schelhammericine and 3-epischelhammericine, are described. Photocycloaddition of a dioxopyrrolobenzazepine to 1-methoxy-3-trimethylsilyloxybutadiene afforded, in a regio- and stereo-specific manner, the cyclobutane derivative, which was converted to a homoerythrinan derivative by utilizing a TBAF-induced 1, 3-anionic rearrangement. The product was transformed into the title alkaloids in several steps.
Synthesis of Erythrina and Related Alkaloids. XXXVI. Studies toward Total Synthesis of Non-aromatic Erythrina Alkaloids. 6. Synthesis of 8-Oxo-.GAMMA.-erythroidine and 8-Oxo-cycloerythroidine, Isomers of the Natural Alkaloids.
A study directed to the total synthesis of β-erythroidine 1, a non-aromatic Erythrina alkaloid, was conducted based on a strategy involving construction of D-furanoerythrinan via Diels-Alder reaction of furodioxopyrroline and the conversion of the resulting furan to the δ-lactone via oxidative fission of the furan ring followed by one-carbon homologation. Oxidation of the furanoerythrinan 17 with N-bromoacetamide followed by treatment with Nafion-H gave the enol γ-lactone 27. Alkaline hydrolysis of 27 followed by methylation with diazomethane gave the keto-ester 31. Alkylation of 31a with dimethylsulfoxonium methylide gave 8-oxo-γ-erythrodine (5). One-carbon homologation of 31a by Yamakawa's method using chloromethyl phenyl sulfoxide resulted in the formation of 8-ozocycloerythroidine (6). Compounds 5 and 6 are structural isomers of natural 8-oxo-β-erthroidine (2).
ANTHRACYCLINES. CYCLOADDITIONS OF 9-CHLORO-10-HYDROXY-1,4-ANTHRAQUINONE WITH VARIOUS BUTA-1,3-DIENES
作者:Nand L. Agarwal、Hans W. Scheeren
DOI:10.1246/cl.1982.1057
日期:1982.7.5
4-anthraquinone (10) affords an efficient, regiospecific access in two steps to tetracyclic ketones (12–14) which have been investigated as intermediates for the synthesis of anthracycline derivatives. Butadienes with a less asymmetric II-electron distribution than 9 give lower regiospecificity in cycloadditions with 10. Depending on the substituents in the used butadiene, the obtained cycloadducts are