Pestalotin synthesis

Perylene-3,4,9,10-bis(dicarbonamide) electrical conductivity, 1, 358 Perylene hexafluoroarsenate conductors, 1, 355 Perylene vat dyes, 1, 336-337 Pestalotin synthesis, 3, 841 Pethidine... 

An example of a chelation-controlled titanium tetrachloride-catalyzed aldol condensation has been featured in a recent synthesis of pestalotin (eq. [86]) (100). The condensation illustrated afforded... 

Midland and Graham completed a total synthesis of (-)-pestalotin (81)33 (Scheme 4.3bb). The asymmetric reduction of the ketone 82 gave the propar-gylic alcohol 83 with high enantioselectivity. Partial reduction of the alkyne,... 

Carlson and Olger have reacted the dilithium salt of propargylic acid with oxiranes and shown that the resulting 8-hydroxycarboxylic acids could be cyclized wiA solvation to 5,6-dihydro-2-pyrones (Scheme 14). The method was subsequently used in a neat synthesis of pestalotin (R = Bu"CHMe). 

The facile conversion of the 6,8-dioxabicyclo[3.2.1]octanes to chiral pyrans is exploited in steps towards the synthesis of ( —)-(6 S, l iS)-pestalotin (478), a gibberellin synergist isolated from microorganisms. Treatment of either tosylate 471 or mesylate 476 with lithium di- -... 

Hagiwara, H., K. Kimura, and H. Uda High Diastereoselection in the Aldol Reaction of the Bistrimethylsilyl Enol Ether of Methyl Acetoacetate with 2-Benzyloxy-hexanal Synthesis of (-)-Pestalotin. J. Chem. Soc. (London) Perkin Trans. 1, 693 (1992). 

Kirihata, M., M. Ohe, I. Ichimoto, and H. Ueda Stereoselective Synthesis of Unnatural Stereoisomers of LL-P880P and LL-P880P, Pestalotin Analogs from Penicillium sp. Biosci. Biotechnol. Biochem., 56, 1825 (1992). 

A general route to 6-substituted valerolactones (112) is by condensation between aldehydes and the dianion derived from butynoic acid followed by hydrogenation using Lindlar s catalyst.During the synthesis of some steroid derivatives, use has been made of an intramolecular Wadsworth-Emmonds procedure to construct an unsaturated valerolactone group (114) from phos-phonate (113) (c/. 3, 87). A new preparation of ( )-pestalotin (115) has as its pivotal step a Lewis acid-catalysed condensation between 2-benzyloxyhexanol and diketen. /3-Ethylenic valerolactones (116) can be obtained from the corresponding /3-allenic acids by treatment with methanolic boron trifluoride (c/. 3, 89). 

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