Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019204 (hepatocellular carcinoma)
 71,386 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Several N-substituted sulfonamides and N'-substituted sulfonylhydrazides have been prepared as sulfur analogues of L-asparagine with the potential of acting as inhibitors of L-asparagine synthetase (ASase, from Novikoff hepatoma). L-Cysteine was converted in known steps to N-carboxy-3-(sulfonylchloro)-L-alanine dibenzyl ester (1). Condensation of 1 with O-benzylhydroxylamine, p-(fluorosulfonyl)benzylamine, or monoethyl fumarylhydrazide (9), followed by deblocking with HF, gave 3-(hydroxysulfamoyl)-L-alanine (3a), 3-[p-(fluorosulfonylbenzyl)]sulfamoyl-L-alanine (3c), and 3-sulfo-L-alanine S-[2-[(E)-3-(ethoxycarbonyl)acryloyl]hydrazide] (3e), respectively. Similarly, 1 with 2-chloroethylamine and deblocking with H2-Pd gave 3-[(2-chloroethyl)sulfamoyl]-L-alanine (3b). tert-Butyl carbazate was allowed to react with 1 and the tert-butyl group was removed with HCl. The resulting sulfonylhydrazide 7 was condensed with p-(fluorosulfonyl)benzoyl chloride and then deblocked with HF to give 3-sulfo-L-alanine S-[2-[P-(fluorosulfonyl)benzoyl]hydrazide] (3d). The inhibition of ASase by 3a-e at 2 mM was 97, 0, 30, 43, and 37%, respectively, and 3a was competitive with L-aspartic acid. Neither 3a nor 3e was effective in increasing the life span of mice bearing P-388 lymphocytic leukemia.
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PMID:Potential inhibitors of L-asparagine biosynthesis. 4. Substituted sulfonamide and sulfonylhydrazide analogues of L-asparagine. 2 54

Asparagine synthetase (L-aspartate:ammonia ligase (AMP-forming, EC 6.3.1.1) activity in rat liver increased when the animals were put on a low casein diet. The enzyme was purified about 280-fold from the supernatant of rat liver homogenate by a procedure comprising ammonium sulfate fractionation. DEAE-Sepharose column chromatography, and Sephadex G-100 gel filtration. The optimal pH of the enzyme was in the range 7.4-7.6 with glutamine as an amide donor. The molecular weight was estimated to be approximately 110,000 by gel filtration. Chloride ion was required for the enzyme activity. The apparent Km values for L-aspartate, L-glutamine, ammonium chloride, ATP, and Cl- were calculated to be 0.76, 4.3, 10, 0.14, and 1.7 mM, respectively. The activity was inhibited by L-asparagine, nucleoside triphosphates except ATP, and sulfhydryl reagents. It has been observed that the properties of asparagine synthetase from rat liver are not so different from those of tumors such as Novikoff hepatoma and RADA 1.
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PMID:Purification and properties of asparagine synthetase from rat liver. 2 63

Several derivatives of erythro-beta-hydroxy-DL-aspartic acid (1) were prepared as a potential inhibitors of L-asparagine synthetase (ASase) from rat Novikoff hepatoma. Benzylation of 1 gave the dibenzyl ester 2 which upon coupling with carbobenzoxyglycine afforded the blocked dipeptide 3. Deblocking of 3 gave glycl-erythro-beta-hydroxyl-DL-aspartic acid (4) which could not be diazotized. The dimethyl ester of 1 was coupled with carbobenzoxyglycine to give the blocked dipeptide 7a which was deblocked to give dimethyl glycel-erythro-beta-hydroxy-DL-aspartate hydrochloride (8). Diazotization of 8 gave impure diazo compound 9 which on reaction with HCl gave the chloro compound 10. The methods of isolation, assay, and inhibition of ASase are discribed. At 10 mM concentrations 10, 1, and its D and L enantiomers inhibit ASase by 45, 47, 36 and 66 percent, respectively.
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PMID:Potential inhibitors of L-asparagine biosynthesis. 2. Chemistry and biological activity of beta-hydroxyaspartic acid and its derivatives. 16 50

The N-[p-(fluorosulfonyl)benzyl] derivatives of L-asparagine and L-glutamine (1a,b) were synthesized as potential inhibitors of L-asparagine synthetase (ASase). Condensation of p-(fluorosulfonyl)benzylamine (2) with the suitably protected amino acid in the presence of dicyclohexylcarbodiimide, followed by deblocking, afforded 1a and 1b. Derivatives 1a and 1b at 10 mM inhibit ASase isolated from Novikoff hepatoma (rats) by 60 and 46%, respectively. Preliminary results on inhibition of Jensen sarcoma (L-asparaginase sensitive) and JA-1 sarcoma (L-asparaginase resistant) tissue cultures by 0.3 mM 1a (139,90%) and 1b (101, 103%), respectively, are discussed.
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PMID:Potential inhibitors of L-asparagine biosynthesis. 3. Aromatic sulfonyl fluoride analogs of L-asparagine and L-glutamine. 24 24

Three electrophilic amide analogues of (S)-2,3-diaminopropionic acid (1, DAP) have been prepared as potential inhibitors of L-asparagine synthetase (ASase, from Novikoff hepatoma, EC 6.3.5.4). DAP was selectively blocked by the carbobenzoxy (Cbz) group to give 3-N-Cbz-DAP (2a). Esterification of 2a with isobutylene afforded tert-butyl 3-N-carbobenzoxy-(S)-2,3-diaminopropionate (3a), which was then blocked at the 2 position with the tert-butoxycarbonyl (Boc) group to give tert-butyl 2-[(S)-(tert-butoxycarbonyl)amino]-3-[(carbobenzoxy)amino]propionate (4). Selective cleavage of the Cbz group by H2/Pd gave the key intermediate tert-butyl 2-N-(tert-butoxycarbonyl)-(S)-2,3-diaminopropionate (5), which was acylated, via the N-hydroxysuccinimide esters, with bromoacetic acid, dichloroacetic acid, and fumaric acid monoethyl ester to give tert-butyl 2-[(S)-(tert-butoxycarbonyl)-amino]-3-(2-bromoacetamido)propionate (6a), tert-butyl 2-[(S)-(tert-butoxycarbonyl)amino]-3-(2,2-dichloroacetamido)propionate (6b), and tert-butyl 2-[(S)-(tert-butoxycarbonyl)amino]-3-(ethoxycarbonyl)acrylamido]-propionate (6c), respectively. Deblocking of 6a-c gave the corresponding amino acids (S)-2-amino-3-(2-bromoacetamido)propionic acid hydrobromide (7a), (S)-2-amino-3-(2,2-dichloroacetamido)propionic acid (7b), and ethyl N-[(S)-2-amino-2-carboxyethyl]fumarate (7c). By a slightly different procedure, 5 was converted in two steps to (S)-2-amino-3-acetamidopropionic acid hydrobromide (7d). The inhibition of ASase by 7a-c at 1 mM was 93, 19, and 37%, respectively, while 7d was without inhibition at 2 mM. Compounds 7a-c failed to increase the life span of mice infected with B16 melanoma.
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PMID:Potential inhibitors of L-asparagine biosynthesis. 5. Electrophilic amide analogues of (S)-2,3-diaminopropionic acid. 678 98