11-Deoxy daunomycinone

Similar results are obtained with the /htetralone derivatives 12, which are useful building blocks in the synthesis of anthracycline antibiotics. Furthermore, the usefulness of the diastereoselec-tive addition to ot-oxo acetals was impressively demonstrated in the synthesis of (-)-7-deoxy-daunomycinone, which uses the completely stereoselective addition of (trimethylsi-lylethynyl)magnesium chloride to the /i-tetraione acetal 12 (R =OMOM R2 = Br) as the key reaction31. 

A 5-deoxy derivative of the above compound has been synthesised in 84% yield as an intermediate towards daunomycinone from the cyclopropane depicted by treatment at ambient temperature in acetic acid with a catalytic quantity of boron trifluoride etherate (ref 189). 

Synthetic approaches to anthracycline antibiotics have been reviewed. Several papers report syntheses of daunorubicin analogues by the glycosidation of daunomycinone derivatives with amino-sugars glycosides of daunomycinone have been prepared from 3-epf-L-daunosamine, D-acosamine, D-daunosamine, D-ristosamine, and 3-ep(-D-daunosamine, and 4-demethoxy-9-deoxy-9-methyl... 

Amino-4-demethoxy-9-deoxy-7-0-(2-deoxy-p-D-ery /iro-pentopyranosyl)-daunomycinone, A-474 2 -Amino-2 -deoxyadenosine, A-328... 

Deoxy-2-0-methyl-of-L-talopyranosyl derivatives of daunomycinone and adriamycinone, made by standard procedures from a fucose precursor, show improved antitumour activity compared with daunorubicin... 

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