1218-34-4Relevant articles and documents
Biosynthesis of violacein: Origins of hydrogen, nitrogen and oxygen atoms in the 2-pyrrolidone nucleus
Hoshino,Takano,Hori,Ogasawara
, p. 2733 - 2741 (1987)
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A fundamental study of amadori rearrangement products in reducing sugar-amino acid model system by electrospray ionization mass spectrometry and computation
Zhang,Ruan,Wang,Ruan,Shao,Aalhus,Juárez
, p. 2941 - 2944 (2014)
It is crucial to characterize Amadori rearrangement products (ARPs) formed in the early stage of Maillard reaction, one of the most important modifications in food science. We setup a reaction model system using six selected amino acids (arginine, asparagines, glutamine, histamine, lysine and tryptophan) and their N-terminal acetylated forms with different reducing sugars for a fundamental study of Amadori rearrangement products. The effects on forming Amadori rearrangement products were studied by using electrospray ionization mass spectrometry (ESI-MS). The reaction rate was affected by reaction temperature, reaction time, property of sugars and amino acids and the fragmentation mechanism of Amadori rearrangement products was illustrated by tandem MS (MS2) with collision-induced dissociation. The proposed fragmentation mechanism of Amadori rearrangement products in MS2 was provided based on MS2 data and it was supported by their computational data of density functional theory (DFT) at the B3LYP/6-31++G(d,p) level.
Comparison of HNO reactivity with tryptophan and cysteine in small peptides
Keceli, Gizem,Moore, Cathy D.,Toscano, John P.
, p. 3710 - 3713 (2014)
Recent discoveries of important pharmacological properties have drawn attention to the reactivity of HNO (azanone, nitroxyl) with biologically relevant substrates. Apart from its role in thiol oxidation, HNO has been reported to have nitrosative properties, for example, with tryptophan resulting in N-nitrosotryptophan formation. We have investigated the reactivity of HNO with tryptophan and small peptides containing either tryptophan or both a tryptophan and a cysteine residue. Our results point to the more reactive nature of cysteine towards HNO compared with tryptophan.
The biosynthetic pathway of crucifer phytoalexins and phytoanticipins: De novo incorporation of deuterated tryptophans and quasi-natural compounds
Pedras, M. Soledade C.,Okinyo-Owiti, Denis P.,Thoms, Ken,Adio, Adewale M.
, p. 1129 - 1138 (2009)
Although several biosynthetic intermediates in pathways to cruciferous phytoalexins and phytoanticipins are common, questions regarding the introduction of substituents at N-1 of the indole moiety remain unanswered. Toward this end, we investigated the potential incorporations of several perdeuterated d- and l-1′-methoxytryptophans, d- and l-tryptophans and other indol-3-yl derivatives into pertinent phytoalexins and phytoanticipins (indolyl glucosinolates) produced in rutabaga (Brassica napus L. ssp. rapifera) roots. In addition, we probed the potential transformations of quasi-natural compounds, these being analogues of biosynthetic intermediates that might lead to "quasi-natural" products (products similar to natural products but not produced under natural conditions). No detectable incorporations of deuterium labeled 1′-methoxytryptophans into phytoalexins or glucobrassicin were detected. l-tryptophan was incorporated in a higher percentage than d-tryptophan into both phytoalexins and phytoanticipins. However, in the case of the phytoalexin rapalexin A, both d- and l-tryptophan were incorporated to the same extent. Furthermore, the transformations of both 1′-methylindolyl-3′-acetaldoxime and 1′-methylindolyl-3′-acetothiohydroxamic acid (quasi-natural products) into 1′-methylglucobrassicin but not into phytoalexins suggested that post-aldoxime enzymes in the biosynthetic pathway of indolyl glucosinolates are not substrate-specific. Hence, it would appear that the 1-methoxy substituent of the indole moiety is introduced downstream from tryptophan and that the post-aldoxime enzymes of the glucosinolate pathway are different from the enzymes of the phytoalexin pathway. A higher substrate specificity of some enzymes of the phytoalexin pathway might explain the relatively lower structural diversity among phytoalexins than among glucosinolates.
Studies on acylase activity and microorganisms. VIII. Enzymatic hydrolysis of 6-N-benzoyl-L-lysine.
KAMEDA,TOYOURA,KIMURA,MATSUI
, p. 394 - 395 (1958)
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Hydrogen/deuterium exchange of cross-linkable α-amino acid derivatives in deuterated triflic acid
Wang, Lei,Murai, Yuta,Yoshida, Takuma,Okamoto, Masashi,Masuda, Katsuyoshi,Sakihama, Yasuko,Hashidoko, Yasuyuki,Hatanaka, Yasumaru,Hashimoto, Makoto
, p. 1129 - 1134 (2014)
In this paper we report here a hydrogen/deuterium exchange (H/D exchange) of cross-linkable α-amino acid derivatives with deuterated trifluoromethanesulfonic acid (TfOD). H/D exchange with TfOD was easily applied to o-catechol containing phenylalanine (DOPA) within an hour. A partial H/D exchange was observed for trifluoromethyldiazirinyl (TFMD) phenylalanine derivatives. N-Acetyl-protected natural aromatic α-amino acids (Tyr and Trp) were more effective in H/D exchange than unprotected ones. The N-acetylated TFMD phenylalanine derivative afforded slightly higher H/D exchange than unprotected derivatives. An effective post-deuteration method for cross-linkable α-amino acid derivatives will be useful for the analysis of biological functions of bioactive peptides and proteins by mass spectrometry.
Catecholamine-induced release of nitric oxide from N-nitrosotryptophan derivatives: A non-enzymatic method for catecholamine oxidation
Kytzia, Anna,Korth, Hans-Gert,De Groot, Herbert,Kirsch, Michael
, p. 257 - 267 (2006)
In recent years, interest in the physiological functions of S-nitrosothiols has strongly increased owing to the potential of these compounds to release nitric oxide. In contrast, little is known about similar functions of N-nitrosated (N-terminal-blocked) tryptophan derivatives, which can be also formed at physiological pH. Utilizing N-acetyl-N-nitrosotryptophan (NANT) and N-nitrosomelatonin (NOMela) as model compounds, we have studied their reaction with catechol and catecholamines such as epinephrine and dopamine. In these reactions, NANT was quantitatively converted to N-acetyltryptophan (NAT), and nitric oxide was identified as a volatile product. During this process, ortho-semiquinone-type radical anions deriving from catechol and dopamine, were detected by ESR spectrometry. The catechol radical concentration was about eight times higher under normoxia than under hypoxia and a similar relationship was found for the decay rates of NANT under these conditions. An epinephrine-derived oxidation product, namely adrenochrome, but not a catechol-derived one, was identified. These observations strongly indicate that N-nitrosotryptophan derivatives transfer their nitroso-function to an oxygen atom of the catecholamines, and that the so-formed intermediary aryl nitrite may decompose homolytically with release of nitric oxide, in addition to a competing hydrolysis reaction to yield nitrite and the corresponding catechol. These conclusions were supported by quantum chemical calculations performed at the CBS-QB3 level of theory. Since nitric oxide is non-enzymatically released from N-nitrosotryptophan derivatives on reaction with catecholamines, there might be a possibility for the development of epinephrine-antagonizing drugs in illnesses like hypertension and pheochromocytoma. The Royal Society of Chemistry 2006.
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Snyder,MacDonald
, p. 1257,1258 (1955)
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Tryptophan derivative and application thereof
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Paragraph 0192-0194, (2020/05/30)
The invention discloses a tryptophan derivative or salt acceptable in feed, a stereoisomer, a tautomer, a solvate and a prodrug molecule of the tryptophan derivative. The tryptophan derivative has a structure shown in a formula (I). The tryptophan derivative as shown in the formula (I) and acceptable salt, stereoisomer, tautomer, solvate and prodrug molecules thereof in the feed all show more stable physicochemical properties than tryptophan in a raw material high thermal stability test and a normal temperature stability test of the feed. The content change of the tryptophan derivative does not exceed the acceptable change range of the feed additive or the feed in the test period; moreover, the compounds can effectively improve the growth of animals, feed conversion and other production performances, even have more excellent improvement effects than tryptophan, and can be used as animal feed additives or used for preparing animal feed additives or animal feeds.
Synthesis and evaluation of oxindoles as promising inhibitors of the immunosuppressive enzyme indoleamine 2,3-dioxygenase 1
Paul, Saurav,Roy, Ashalata,Deka, Suman Jyoti,Panda, Subhankar,Srivastava, Gopal Narayan,Trivedi, Vishal,Manna, Debasis
, p. 1640 - 1654 (2017/08/22)
Indoleamine 2,3-dioxygenase 1 (IDO1) is considered as an important therapeutic target for the treatment of cancer, chronic infections and other diseases that are associated with immune suppression. Recent developments in understanding the catalytic mechanism of the IDO1 enzyme revealed that conversion of l-tryptophan (l-Trp) to N-formylkynurenine proceeded through an epoxide intermediate state. Accordingly, we synthesized a series of 3-substituted oxindoles from l-Trp, tryptamine and isatin. Compounds with C3-substituted oxindole moieties showed moderate inhibitory activity against the purified human IDO1 enzyme. Their optimization led to the identification of potent compounds, 6, 22, 23 and 25 (IC50 = 0.19 to 0.62 μM), which are competitive inhibitors of IDO1 with respect to l-Trp. These potent compounds also showed IDO1 inhibition potencies in the low-micromolar range (IC50 = 0.33-0.49 μM) in MDA-MB-231 cells. The cytotoxicity of these potent compounds was trivial in different model cancer (MDA-MB-231, A549 and HeLa) cells and macrophage (J774A.1) cells. Stronger selectivity for the IDO1 enzyme (124 to 210-fold) over the tryptophan 2,3-dioxygenase (TDO) enzyme was also observed for these compounds. These results suggest that the oxindole moiety of the compounds could mimic the epoxide intermediate state of l-Trp. Therefore, the structural simplicity and low-micromolar inhibition potencies of these 3-substituted oxindoles make them quite attractive for further investigation of IDO1 function and immunotherapeutic applications.
