Anthraquinone antibiotics synthesis

The addition-protonation procedure maintains the arene-chromium bond and allows further application of the activating effect of the metal. In an approach to the synthesis of anthraquinone antibiotics, the dihydronaphthalene complex (79) was allowed to react with a cyanohydrin acetal anion and then quenched with acid.129 The resulting tetralin complex (80) could be metallated effectively and carried on to a key intermediate (81) in anthraquinone construction (equation 54)... 

There is much interest in anthrapyran antibiotics. Synthesis of S-indomycinone indicates that a revision is required <07CEJ9939>. A total synthesis of racemic y-indomycinone 49 based on a Baker-Venkataraman rearrangement of the anthraquinone ester 47 and cyclisation of the resulting diketone to the chromone 48 has been reported <07EJ01905>. A total synthesis of the structurally simpler topopyrone C involves similar methodology <07TL1049>. In an alternative approach which is readily adaptable to the synthesis of other anthrapyrans, the... 

A synthesis of the chlorinated angucycline antibiotic BE-23254 (1686), which was isolated from Streptomyces sp. A 23254, has confirmed the structure of this benz[a anthraquinone derivative (1644,1939,1940). Two detailed examinations of the rare Australian soil actinomycete Kibdelosporangium sp. uncovered a series of... 

In connection with a synthesis of 11-deoxydaunomycinone [35] we did not observe the expected linear cyclization of the bromide 21, but rather the exclusive angular cyclization to the benzo[u]anthraquinone (22) [36]. This reaction was later exploited in the synthesis of a daunomycinone-rabelomycin hybrid 24 which incorporated structural elements of both antibiotics [37]. The required bromide 21 was prepared by alkylation of a bromomethylanthraquinone... 

The phthalides occur in several natural products . They are also intermediates for the synthesis of a variety of natural products like naphthols, anthraquinone natural products, anthracyclic antibiotics, the phthalide isoquinolines, protoberberine alkaloids etc. 

A review of the synthesis of anthracyclinones by elaboration of anthraquinones includes a section on the use of sugars as chiral templates. Glycosylations of the daunomycinones (46)-(48) led to the corresponding daunomycin derivatives (49)-(51). The L-fyxo-, L-arabino- and L-nfeo-isomers of the isorhodomycin compounds (52) have been made and tested for cytotoxicity. Several analogues of the anthracycline antibiotics, eg. (53), having a 1,2,3-triazolyl moiety in the sugar, have been described. ... 

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