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Research describes the first time synthesis of an oligomeric procyanidins possessing 4alpha-linked epicatechin units by reacting the protected 4-ketones with aryllithium reagents obtained by halogen/metal exchange from the aryl bromides.

Results demonstrate that procyanidin B(sub)2 exhibits a 4beta,8 interflavan bond. A procedure for an exhaustive deoxygenation of a single flavonoid in a partially protected dimeric structure is described.

(+)-catechin was transformed into 5,7,3',4'-tetra-O-benzyl-(-)-epicatechin via benzylation of phenolic oxygens.

The benzylation of all hydroxyl groups except OH-1 in D-3-deoxy-3-fluoro-and D-3-chloro-3-deoxy-myoinositol, obtained from L-quebrachitol, yields the D-3-deoxy-3-fluro-(FPI) and D-3-chloro-3-deoxy (CPI) analogues of phosphatidylinositol. FPI is more active and lacks selectivity for wild type murine NIH 3T3. CPI is as inactive as FPI's simplified analogue. The inositol analogues are moderately and highly selective during growth inhibition of v-sis transformed and wild type NIH 3T3 cells, respectively.

Investigates polyphenol chemistry and bioactivity of epicatechin units through stereoselective synthesis. Preparation of prototypical dimer, epicatechin-4alpha,8-epecatechin; Removal of 4-hydroxyl group resulting tertiary benzylic alcohol 27a,b; Use of compounds 14 and 17 containing phloroglucinol trimethyl ether.

Examines the establishment of interflavan linkage regio- and stereochemistry by oxidative degradation of an ortho-alkylated derivative of procyanidin B2 to (R)-(-)-2,4-diphenylbutyric acid. Removal of the C-3 alcohol functions; Deprotection of the top unit by hydrogenolysis; Aryl triflate formation; Selective oxidation of the bottom unit.