Synthesis of Perylenequinone

The perylenequinone natural product calphostin D 3 is of much current interest due to its potent inhibition of protein kinase-C. The key step in an elegant and very short total synthesis of 3 was the treatment of the o-quinone 1 with TFA and then TTFA, which gave 2 in 91% yield. 

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The direct conversion of nitroalkenes into ketones is especially useful for the preparation of arylacetones. They are readily prepared by the condensation of aromatic aldehydes with nitroethane and by the subsequent Nef reaction. "Typical examples are presented in Eq. 6.22 and Eq. 6.23 the product of Eq. 6.23 is used for total synthesis of perylenequinone, calphosdn D, which is a potent inhibitor of protein kmase C. "... 

Stereoselective synthesis of perylenequinones. Synthesis of the symmetrical perylenequinone phleichrome (4) has been effected by coupling of two identical naphthalene units to provide a binaphthol, which is then oxidized to a perylenequinone. Thus the bromonaphthalene 1 on halo-lithium exchange (f-BuLi) followed by reaction of anhydrous FeCl3 dimerizes to two optically active binaphthyls, (+)-and (— )-2, with 3 1 diastereoselectivity. 

Scheme 7.22 Synthesis of C3,C3 -substituted C7,C7 -propyl perylenequinone analogs...

Diels-Alder reactions of 1235 synthesis of 1228, 1231, 1250, 1335 Quinone oxime tautomers 251, 252 Quinones—see also Aminoquinones, Anthraquinones, Arenolquinones, Benzoquinones, CaUxquinones, Hydroquinones, Hydroxyquinones, Naphthoquinones, Perylenequinones, Scabequinone reduction of 1108 Quinone units 1396... 

Compounds 738-740 belong to the class of perylenequinones (474), but until now, there has been no approach to the total synthesis of altertoxins, based oti the difficulty in formation of two neighboring but separate aromatic centers. 

This catalytic system operating on less electron-rich 2-naphthols complements well more traditional systems working on highly electron-rich naphthols, which have been employed in the synthesis of chiral perylenequinones-based derivatives that are potent protein kinase C inhibitors and are promising agents for photodynamic cancer therapy. ... 

The common denominator for all the previous approaches to the perylenequinones is a diastereoselective oxidative coupling of homochiral 2-naphthols. Our group proposed an alternative enantioselective convergent synthesis that would greatly... 

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