5 -Benzoyl-2-benzyl

Those bearing a substituent with more than six carbon atoms except for an unsubstituted benzoyl, benzyl, benzylidene, phenethyl, phenylethynyl, or styryl group... 

However, benzoyl chlorides and sodium telluride under these conditions gave benzoyl benzyl tellurium1 and not dibenzoyl tellurium (p. 560). 

DDQ. a reagent typically used to deprotect p-methoxybenzyl ethers (see section 4.3 4), has been used for the deprotection of acetals19 and thioacetals.20 The use of 0.1 -0.4 equivalents of DDQ in acetonitrile-H20 (9 1) cleaves isopropylidene groups at room temperature to 80 C without affecting p-toluenesulfonyl, benzoyl, benzyl, or acetate groups. Monosubstituted dioxolanes [Scheme 3.17]21 are more readily hydrolysed than bicyclic, spirocyclic, and disubstituted systems and 1,3-dioxanes are more labile than 1,3-dioxolanes. Removal of dithioacetals requires 2 equivalents of DDQ at 80 °C... 

Benzophenone 2-[Benzoyl-benzyl (bzw. allyl)-amino]-5-chlor-E6b/1, 659 (NH - N —R)... 

OH free Here, for all the three monosaccharides, a derivative with the 4-OH free can be obtained from the 4,6-O-benzylidene derivative through regioselective reductive opening. Formation of the 4,6-acetal with consecutive 2,3-protection (acetylation, benzoylation, benzylation) and reductive opening using various reagents yields the desired compounds. In mannosides, the selective formation of the 4,6-6>-acetal is not trivial, but can be accomplished with a 50 to 70% yield. 

Methylquinazolin-4(3//)-one was obtained in over 62% yield by reacting the phosphorane (25) with sodium hydride in methyl cyanide. The phos-phorane was readily formed from anthranilamide and prop-2-ynyltriphenyl-phosphonium bromide. When anthranilamide was fused with benzoin and a trace of acid at 150°C, it gave 2-phenylquinazolin-4(3H)-one together with o-iV-(a-benzoyl benzyl)aminobenzamide. The latter was cyclized, with ethyl orthoformate, to l-(a-benzoylbenzyl)quinazolin-4-one. If anthranilamide and benzoin were boiled in benzene with azeotropic removal of water, then the Schiff base (26) was formed. This gave 2-phenylquinazolin-4(3Jf/)-one and benzoic acid on heating alone at 150°C or with ethyl orthoformate. The mechanism of this reaction is not clear unless a retro-benzoin condensation and oxidation are occurring. 

As D-xylose and L-arabinose are 4-epimers, both, as well as mixtures of them (as provided by hemiceUulose), can be used to prepare enantiomerically pure synthetic intermediates the center C(4) of which is deoxy or sp -hybridized (alkenes, ketones). For instance, treatment of pure o-xylose with acetone under acidic conditions, followed by selective C(5) benzoylation, benzylation of the 3-alcoholic moiety, hydrolysis of the benzoate, and iodination furnishes the 5-iodo derivative... 

Specific functionalization of a polyamine requires selective protection of the various amine groups. Other protecting groups, in addition to tosyl, include benzoyl, benzyl, and mesyl. Lehn and co-workers have prepared tri-aminodiols with mixed blocking groups (Flosseini et al., 1987). 

Deacetalization. Selectivity of deacetalization has been observed. The method is - rmpatible with acetyl, benzoyl, benzyl, and tosyl protecting groups. 

Benzyl glycoside, N-benzoyl Benzyl 2-benzamido-2,5-dideoxy-a-D-ribofurano-side... 

O-Isopropylidene, 4-benzoyl Benzyl 2-benzamido-2-deoxy-4,6-0-isopropyli-dene-p-D-glucopyranoside C23H27N0 413.469... 

Tri-Me, H-benzoyl Benzyl 2-benzamido-2-deoxy-3,4,6-tri-O-methyl-p-D-glucopyranoside... 

O-Isopropylidene, 2-benzoyl Benzyl 2-0-benzoyl-3,4-0-isopropylidene-p-L-arabinopyranoside... 

O-Isopropylidene, 6-benzoyl Benzyl 6-0-benzoyl-3,4-0-isopropylidene-P-D-galactopyranoside [16741-12-1]... 

O-Benzylidene, 3-benzoyl Benzyl 3-0-benzoyl-4,6-0-benzylidene-P-D-galac-topyranoside... 

Benzyl glycoside, 3-benzyl, 2, 3, 5,5 -tetra-benzoyl Benzyl 5-0-benzoyl-3-0-benzyl-2-0-(2,3,5-triA3-benzoyl-p-D-ribofura-nosyl) -p-D-ribofuranoside [93215-14-6]... 

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