Derived from Aspartate

A number of P-chirogenic diaminophosphine oxides (DIAPHOXs) 275 derived from aspartic acid were prepared via hydrolysis of triaminophosphine intermediate 274, generated in a fully diastereoselective reaction of triamines 273 with phosphorus trichloride (Scheme 65) [102, 103],... 

Asparagine is derived from aspartic acid. Its side chain is an amide. 

The pyrimidine ring is made up of three components the nitrogen atom N-1 and carbons C-4 to C-6 are derived from aspartate, carbon C-2 comes from HCOa", and the second nitrogen (N-3) is taken from the amide group of glutamine. 

Regioselective enolization toward the nitrogen-bearing carbon in an oxazolinyl-methyl ketone derived from aspartic acid has been observed [48], The nitrogen atom of the heterocycle is conjoint with the carbonyl, therefore the creation of a conjugate system via enolization is favorable. 

FIGURE 22-22 Interlocking regulatory mechanisms in the biosynthesis of several amino acids derived from aspartate in E. coli. Three... 

A. Fixation of N, and the Nitrogen Cycle 1383 D. Compounds Derived from Aspartate... 

Using the dianionic ligand derived from aspartic acid, H02CCH2CH(NH2)C02H, the complex [Ni(L-aspartato)(H20)2]H20 has been synthesized and its structure determined... 

Figure 13.11. Formation and hydrolysis of succinimides derived from aspartic acid. Table 13.20. Preparation of imides and related compounds.

Biosynthesis of UMP. The parts of the intermediates derived from aspartate are shown in red. Bold type indicates atoms derived from carbamoyl phosphate. In contrast to purine nucleotide synthesis, where ring formation starts on the sugar, in pyrimidine biosynthesis the pyrimidine ring is completed before being attached to the ribose. 

The type ac ring-construction process relies upon the reaction of a 1,3-diamine with a two-carbon electrophile, readily available fragments that offer simplicity in reaction design. The reaction of 2-aminobenzylamine with the reactive diketonitrile 75, derived from aspartic acid, in CH2CI2 proceeded smoothly to furnish the l,4-benzodiazepin-3-one 76... 

Native CPMV particles display reactive lysines [82], carboxylates derived from aspartic and glutamic acid [83], and tyrosines [84] on their exterior solvent-exposed surface (Figure 9.4). They further display reactive interior cysteines residues [79],... 

In the context of my PhD research with Drs. Dave Evans and George Lomonos-soff we have demonstrated that CPMV also displays addressable carboxylates on its solvent-exposed surface (Figure 9.4b) [83]. The structural data from CPMV suggest eight to nine carboxylate groups, derived from aspartic and glutamic acids, to be on the solvent-exposed exterior surface five on the S subunit, two on the L subunit, and the carboxy-terminus of the solvent exposed terminal domain of S. 

Nitrogen incorporated into urea in the Ever originates from both intrahepatic and extrahep-atic sources. Urea contains two nitrogen atoms one is derived from ammonium, while the other is derived from aspartic acid. In Ever hepato-cytes, ammonium is generated by the oxidative deamination of glutamic acid, catalyzed by glutamate dehydrogenase,... 

An elegant modular synthesis of the 52 scaffold originates from methionine, which is transformed to isothiocyanate 54 by standard operations (Scheme 14) [31]. Condensation with an appropriate 1,3-diamine, here 55 derived from aspartate, is followed by exhaustive S-methylation inducing a smooth double ring closure. After deproteetion, guanidine 58 was isolated in gratifying 85 % yield. 

Hexenyl radicals cyclize to cyclopentylmethyl radicals (see Volume 4, Chapter 4.2). Thus radical decarboxylation of 6-heptenoic acids, by whatever means, usually results in die formation of five-mem-v beied rings. Although this fact had been appreciated previously it is only recendy, widi the advent of the 0-acyl thiohydroxamates, that it has been exploited from a syndietic point of view. An example is provided by the synthesis of bicyclo[4.3.0]proline derivatives from aspartic acid carried out by the Barton group (equation 51). It will be noted that activation of die C—C double bond acting as a radical trap is not necessary in these intramolecular reactions. 

A recent example by McGarvey demonstrates the formation of chiral derivatives (73)-(76) which are useful for elaboration into the ubiquitous propionate unit through stereoselective enolate-based alkylation (equation 56)." The thiol ester substrates were derived from aspartic acid in seven steps. The acylation of either dimethylcuprate or the Grignard-derived organocopper reagent was extremely clean when these organometallics were used in excess. No epimerization of the adjacent center was observed during the addition. 

A. When argininosuccinate is cleaved to form arginine, the carbons that were derived from aspartate are released as fumarate and the nitrogen of aspartate is incorporated into arginine. 

The nitrogen atom in (109) was shown to be derived from aspartate by incorporation of dl-[2- C, 5N]aspartic acid [88]. In the NMR spectrum of the enriched metabolite, the signal corresponding to the C-3 methylene carbon was observed (Fig. 14) as a broad singlet due to A" with N attached and a sharp doublet (7cn Hz). The presence of the doublet, offset to lower frequency by the associated isotope shift, confirmed the intact incorporation of the C-N bond from aspartate. The origin of the oxygen atoms was elegantly demonstrated by fermentation under an atmosphere of 03 (1 1) in a defined... 

During the scale-up of an asymmetric synthesis of lotrafiban 228, a drug for the prevention of thrombotic events , racemisation proved to be a problem. The synthesis used the chiral pool strategy (chapter 23), the fragment in the frame of the intermediate 229 being derived from aspartic acid. 

Conversion of inosinate to adenylate requires the insertion of an amino group derived from aspartate (Fig. 

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