Dibenzoyl derivative

A) Benzoyl Derivative. Since acetylation and benzoylation do not always proceed smoothly with nitrophenols, it is best to reduce them to the aminophenol as in (3) above. Add an excess of 20% aqueous sodium hydroxide to the reaction mixture after reduction, cool and then add a small excess of benzoyl chloride, and shake in the usual way. The dibenzoyl derivative wiU separate. Filter, wash with water and recrystalUse. (M.ps., p. 551.)... 

The dibenzoyl derivatives can be prepared by the normal Schotten-Baumann method, using 10% aqueous sodium hydroxide and an excess of benzoyl chloride, but the m.ps. of the dibenzoyl derivatives are inconveniently high (p- ssO-... 

Nitroamlines. Acetyl derivatives (p. 388), Benzoyl derivatives (p. 388). Diamines. Diacet> l derivatives (p. 388), Dibenzoyl derivatives (p. 388). Halogeno-hydrocarbons, a-Naphthyl ethers (from reactive halogen compounds, p. 391, and their Picratcs, p. 394), Nitro-derivatives (p.39i). Carboxylic acid (if oxidisable side chain) (p. 393). 

Neutrahse about one third of the filtrate with 5N sodium hydroxide and add a further 2 ml. of the alkah solution. Add 1 ml. of benzoyl chloride and stir until the odour of the acid chloride disappears. Collect the solid by suction filtration, wash it with water until free from alkah, and then recrystalhse it from dilute alcohol. The product is the dibenzoyl derivative of hexamethylenediamine and melts at 159°. 

Lobelanidine, C22ll2g02N. Crystallises from alcohol in laminae, m.p. 150°, [ ] D i 0°, distils unchanged in a vacuum and is readily soluble in acetone or benzene, sparingly so in ether. The hydrochloride, m.p. 135-8°, forms needles from alcohol the hydrobromide has m.p. 188-190°. The dibenzoyl derivative melts at 109-10° and the hydrochloride of the diacetyl derivative at 214-5°. The methiodide becomes tiu-bid at 178-5° and clears at 200°. Phosphorus trichloride converts the base into dichlorolobelane... 

HjO), a picrate, m.p. 253° (dec.) and furnishes a dibenzoate, whose sulphate has [a] ° + 52-1° (EtOH) and hydrochloride, B. HCl. 2H2O, m.p. 115° or 205° (dry), + 41-8° (dilute alcohol) and nitrate, B. HNO3, m.p. 197°. On reduction with hydriodic acid and red phosphorus the dihydroxytropane is converted into tropane and on treatment with phosphorus oxychloride it yields a base, CgHjgON, b.p. 188°/752 mm., picrate, m.p. 177° (dec.). This dihydroxytropane is probably represented by formula (XIII).The dibenzoyl-derivative has local ansesthetic properties. The wovaleryl ester is the alkaloid valeroidine found in Duboisia myoporoides (p. 90). 

Anhalamine, C11H15O3N, occurs in microscopic needles, m.p. 187-8°. The hydrochloride, B. HCl. 2HjO, forms lustrous leaflets, m.p. 256-8° and the sulphate, Bg. H2SO4, colourless prisms the picrate has m.p. 234-6°. The base contains two methoxyl groups and one hydroxyl group. A dibenzoyl derivative, m.p. 128-9°, and a monobenzoyl derivative, m.p. 167-5°, are formed, the latter but not the former being soluble in alkalis. The methyl ether of anhalamine is identical with anhalinine, b.p. 130 0°/0-01 mm., m.p. 61-3°, and the A-methyl derivative is anhalidine, m.p. 131-3°. 

Diversine, C2oH2,05N Pamsinomenine). This base was obtained by Kondo, Ochiai and Nakajima as an amorphous, yellow substance, m.p. 80-93°, [a]n ° + 6-98°. It reduces solutions of gold or silver salts. The hydrochloride is amorphous, m.p. 135-140° (dec.), as is also the methio-dide. The alkaloid contains two methoxyl groups and one methylimino-group, and with benzoic anhydride yields a mixture of mono- and dibenzoyl derivatives. For another diversine, see p. 350. 

Heliotridine, CgHjgOgN, m.p. 116-5-118°, [aju +31° (MeOH), forms a hydrochloride, m.p. 122-4°, and a dibenzoyl derivative hydrochloride, m.p, 180°. The latter on hydrogenation is converted into the non-crystalline hydroxyheliotridane benzoate. 

The dibenzoyl derivative, m.p. 98-9°, of the latter on controlled, alkaline hydrolysis yields a mixture of two monobenzoylMoamylputre-scines, separated as the hydrochlorides, of which (A), m.p. 92-3°, on treatment with nitrous acid followed by acid hydrolysis gives isoamyl-... 

Allyl-pyrocatechol, CgHj O, exists in betel leaf oil. It is a crystalline body melting at 48° to 49° and boiling at 139° at 4 mm. It yields a dibenzoyl derivative melting at 71° to 72°. Its constitution is as follows —... 

Anhydro-D-mannitol is also obtained by a novel route from 1,6-dibenzoyl-D-mannitol. When this compound is heated with p-tolu-enesulfonic acid in acetylene tetrachloride, it suffers partial dehydration and one of the products is a dibenzoyl derivative of mannitan. On debenzoylation of this substance it yields crystalline 1,4-anhydro-D-mannitol.67 The formation of dibenzoyl-1,4-anhydro-D-mannitol has involved the migration of at least one benzoyl group and Hockett and coworkers6 believe that the initial product is either 2,6- or 3,6-dibenzoyl-1,4-anhydro-D-mannitol. 

Hippuric acid is a normal product of metabolism. It is produced in the kidney by the enzymic union of benzoic acid and glycine (Schmiede-berg and Bunge, 1877). In birds benzoic acid is rendered innocuous by combination with ornithine (aS-diamino-valeric acid) to form the dibenzoyl-derivative, so-called ornithuric acid (Jaffe). 

On occasion such reductive deprotection processes can be quite selective. Electrochemical reduction of A,A -di-p-toluenesulfonyl-A-t-butoxycarbonyl derivatives of aliphatic and aromatic diamines selectively removed the p-toluenesulfonyl group attached to a primary amine site63. Yields on the mono-protected products are fair to high selective deprotection of the corresponding A,A -dibenzoyl derivatives occurred in yields >92%. 

A variety of procedures were utilized to analyze this reaction mixture and to characterize a,10-diaminopolystyrene. Thin layer chromatographic analysis using toluene as eluent exhibited three spots with Rf values of 0.85, 0.09, and 0.05 which corresponded to polystyrene, poly(styryl)amine and a,w-diaminopolystyrene (see Figure 1). Pure samples of each of these products were obtained by silica gel column Chromatography of the crude reaction mixture initially using toluene as eluent [for polystyrene and poly(styryl)amine] followed by a methanol/toluene mixture (5/100 v/v) for the diamine. Size-exclusion chromatography could not be used to characterize the diamine since no peak was observed for this material, apparently because of the complication of physical adsorption to the column packing material. Therefore, the dibenzoyl derivative (eq. 5) was prepared and used for most of the analytical characterizations. 

Cyclization of 820 with acetamidine gave 824. The phenyl analog 825 was prepared from 818 by benzoylation to give the respective dibenzoyl derivative, whose alkylation gave the corresponding 9- and 7-alkylated... 

However, the dehydration of two N-acyl amidoximes is reported. In the first example, the dibenzoyl derivative of oxyguanidine (X) has been transformed by hydrolysis into 3-amino-5-phenyloxadiazole but the postulated intermediate, N-benzoylaminoformamidoxime (XI) was not isolated (2,121), and the formation of the O-benzoyl intermediate would be more probable. 

Due to the complexity of conformational equilibria, the application of the dibenzoate chirality rule to determination of the absolute configuration of acyclic diols and polyols requires cautious evaluation of the CD data. For example, (0,0)-dibenzoyl derivatives of diesters and N.N.N ,AT-tetraalkyldiamides of (/t,f )-tartaric acid give exciton Cotton effects of opposite sign due to the preference of diesters for a planar and tetraalkyldiamides for a gauche conformation of the carbon chain176. 

Acylation of 3-hydroxy-l,2,4-thiadiazoles (184) by the usual procedures yields monosubstitution products that are formulated as phenolic esters (e.g. 185 R = Ph R = Ac, Bz, or p-MeC6H4S02)178 (see also ref. 130). 5-Anilino-3-hydroxy-1,2,4-thiadiazole affords diacetyl and dibenzoyl derivatives one acyl residue being assumed to enter the hydroxyl group, the possible structures of the derivatives are 186a-c.130... 

The absolute stereochemistry of forskolin (45) and of the C(6) and C(j) dibenzoyl derivative (46) was unequivocally assigned by applying the exciton chirality method, thus placing R3 (OAc in 45) substituent at -position134. 

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