N-Tricarboxylic ester

In a 3-1. round-bottomed flask equipped with a reflux condenser are placed 582 g. (2.5 moles) of N-tricarboxylic ester (p. 60) and 800 g. (6.7 moles) of 42% hydrazine hydrate (Note 1). The flask is shaken by hand to mix the two layers. After a short time, reaction begins with considerable evolution of heat, and all the N-tricarboxylic ester goes into solution (Note 2). After the reaction subsides, the solution is heated for 1 hour on a steam bath and then evaporated under reduced pressure until the mixture becomes a thick slurry of diaminobiuret crystals (Note 3). The mixture is cooled, 2 1. of 95% ethanol is added, and the diaminobiuret which has crystallized is filtered, washed with 250 ml. of ethanol, and dried. The substance melts at 205° with decomposition. The yield is 115-125 g. (69-75%). 

Diaminobiuret has been prepared only from N-tricarboxylic ester and hydrazine hydrate.1 Ethyl hydrazinecarboxylate has been prepared by reduction of nitrourethan electrolytically2 or with zinc dust and acetic acid,3 and by the action of hydrazine hydrate on diethyl carbonate,4 6 ethyl chlorocarbonate,6 and N-tricarboxylic ester.1... 

In the presence of sodium, further acylation of ethyl carbamate by chloroformic ester gives ethyl N-tricarboxylate, N(C0jCjHs)3, in 57% yield."... 

A new erythrina alkaloid, erythroculine, from Cocculus laurifolius has been shown to have the structure (167). The ester group may be reduced with lithium aluminium hydride and the acetyl ester of the resulting alcohol on treatment with cyanogen bromide affords the hindered diphenyl (168), with loss of hydrogen bromide and methanol. This on reduction to the secondary base, N-methylation, and successive Hofmann degradations affords an olefin that may be oxidised to the tricarboxylic acid (169).The base represents a novel structure in having the additional carbon atom linked to the ring system. 

The total synthesis of (+ )-dehydroheliotridine (4), a toxic metabolite of the pyrrolizidine alkaloids (e.g. lasiocarpine and heliotrine), has also been described.2 The pyrrole ring was obtained by reaction of l,6-dihydroxy-2,5-dicyanohexa-l,3,5-triene-l,6-dicarboxylic ester (5) with j3-alanine, which afforded the N-substituted pyrrole ester (6), together with the appropriate amide of oxalic acid. Careful hydrolysis of (6) with dilute alkali afforded the related tricarboxylic acid, which was converted, by Dieckmann cyclization, hydrolysis and decarboxylation, into the keto-acid (7). Esterification of (7) with diazomethane, followed by reduction with lithium aluminium hydride, finally afforded ( )-dehydroheliotridine (4), identical, except in optical rotation, with dehydroheliotridine obtained earlier by Culvenor et al.3... 

ADK CIZER C-8 1,2,4-Benzenetricarboxylic acid, trioctyl ester Benzene tricarboxylic acid, trioctyl ester Diplast TM Diplast TM8 EINECS 201-877-4 HSDB 5263 JayBex TOTM Kodaflex TOTM Nuopiaz 6959 PX 338 TOTM Tri (2-ethylhexyl) trimellitate Tri-n-octyl trimellitate Trimex N 08 Trioctyl trimellitate Nuopiaz TOTM Palatinol TOTM Plasthall TOTM PX-338 Staflex TOTM Uniflex TOTM. Plasticizer Solid d = 0.989 bp = 414°. Exxon ExxonMobil Chem. Co. 

It is worth noting that the C-N-C-C fragment can be derived from heterocyclic compounds. For instance, interaction of triethyl l,3,5-triazin-2,4,6-tricarboxylate 269 with arylhydrazines affords esters of 5-amino-6-oxo-l,6-dihydro-l,2,4-triazin-3-carboxylic acid 270 in good yields (Scheme 160) <2004TL2791>. 

Decalin-l,8-diones. Trimethyl propane-1,1,3-tricarboxylate and cyclohex-l-en-3-one added to a soln. of Mg in hot abs. methanol, refluxed 1 hr., the solvent removed by distillation, abs. benzene added repeatedly if necessary and benzene distilled until the b.p. of the distillate reaches 79° dimethyl decalin-l,8-dione-4,4-dicarboxylate. Y 15% based on startg. ester consumed. K. Schank and N. Moell, B. 102, 71 (1969). 

Acetyl-CoA is the hub of carbohydrate metabolism and has a central position in overall metabolism. Products of carbohydrate, fat and protein metabolism are channeled via acetyl-CoA into oxidative degradation in the tricarboxylic acid cycle. The acetyl residue is used in the synthesis of esters and amides (e.g. acetylcholine, Af-acetylglucosamine, N-acetylgluta-mate). Acetyl-CoA is also the starting point for iso-prenoid synthesis via mevalonic acid and for fatty acid synthesis. 

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