Exact Mass: 187.049408
Exact Mass Matches: 187.049408
Found 500 metabolites which its exact mass value is equals to given mass value 187.049408
,
within given mass tolerance error 0.05 dalton. Try search metabolite list with more accurate mass tolerance error
0.01 dalton.
6-Chloro-N-(1-methylethyl)-1,3,5-triazine-2,4-diamine
C6H10ClN5 (187.06246900000002)
CONFIDENCE standard compound; INTERNAL_ID 1296; DATASET 20200303_ENTACT_RP_MIX504; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 7123; ORIGINAL_PRECURSOR_SCAN_NO 7121
CONFIDENCE standard compound; INTERNAL_ID 1296; DATASET 20200303_ENTACT_RP_MIX504; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 7114; ORIGINAL_PRECURSOR_SCAN_NO 7112
CONFIDENCE standard compound; INTERNAL_ID 1296; DATASET 20200303_ENTACT_RP_MIX504; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 7136; ORIGINAL_PRECURSOR_SCAN_NO 7132
CONFIDENCE standard compound; INTERNAL_ID 1296; DATASET 20200303_ENTACT_RP_MIX504; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 7127; ORIGINAL_PRECURSOR_SCAN_NO 7125
CONFIDENCE standard compound; INTERNAL_ID 1296; DATASET 20200303_ENTACT_RP_MIX504; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 7139; ORIGINAL_PRECURSOR_SCAN_NO 7137
CONFIDENCE standard compound; INTERNAL_ID 1296; DATASET 20200303_ENTACT_RP_MIX504; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 7129; ORIGINAL_PRECURSOR_SCAN_NO 7127
6-Chloro-N-(1-methylethyl)-1,3,5-triazine-2,4-diamine is a major soil metabolite of Atrazine
Amrinone
Amrinone is only found in individuals that have used or taken this drug. It is a type 3 pyridine phosphodiesterase inhibitor. It is used in the treatment of congestive heart failure.Amrinone is a phosphodiesterase inhibitor (PDE3), resulting in increased cAMP and cGMP which leads to an increase in the calcium influx like that caused by beta-agonists resulting in increased inotropic effect.
Amrinone
C - Cardiovascular system > C01 - Cardiac therapy > C01C - Cardiac stimulants excl. cardiac glycosides > C01CE - Phosphodiesterase inhibitors D004791 - Enzyme Inhibitors > D010726 - Phosphodiesterase Inhibitors > D058987 - Phosphodiesterase 3 Inhibitors C78274 - Agent Affecting Cardiovascular System > C29707 - Vasodilating Agent D002317 - Cardiovascular Agents > D002121 - Calcium Channel Blockers D002317 - Cardiovascular Agents > D014665 - Vasodilator Agents C471 - Enzyme Inhibitor > C744 - Phosphodiesterase Inhibitor D020011 - Protective Agents > D002316 - Cardiotonic Agents D000077264 - Calcium-Regulating Hormones and Agents D049990 - Membrane Transport Modulators
Indoleacrylic acid
Indoleacrylic acid (CAS: 1204-06-4), also known as indoleacrylate, IA, and IAcrA, is a member of the class of compounds known as indoles. Indoles are compounds containing an indole moiety, which consists of pyrrole ring fused to benzene to form 2,3-benzopyrrole. Indoleacrylic acid is practically insoluble (in water) and a weak acidic compound (based on its pKa). Within the cell, indoleacrylic acid is primarily located in the membrane (predicted from logP). Indoleacrylic acid is best known as a plant growth hormone (a natural auxin), whereas its biological role in animals is still unknown. A two-stage production of this compound is likely: intestinal microorganisms catabolize tryptophan to indole derivatives which are then absorbed and converted into indoleacrylic acid and its glycine conjugate, indolylacryloylglycine (IAcrGly). Indolylacryloylglycine excretion in urine is especially pronounced in some myopathies, namely in boys with Duchenne muscular dystrophy (PMID: 10707769). It has been recently found that indoleacrylic acid promotes intestinal epithelial barrier function and mitigates inflammatory responses. Stimulating indoleacrylic acid production could promote anti-inflammatory responses and have therapeutic benefits (PMID: 28704649). Urinary Indole-3-acrylate is produced by Clostridium sporogenes (PMID: 29168502). Indoleacrylic acid is also a metabolite of Peptostreptococcus (PMID: 28704649, 29168502). trans-3-Indoleacrylic acid is an endogenous metabolite.
1-(Malonylamino)cyclopropanecarboxylic acid
1-(Malonylamino)cyclopropanecarboxylic acid is found in cereals and cereal products. 1-(Malonylamino)cyclopropanecarboxylic acid is a constituent of numerous plant species including wheat, tomato and sweet corn Constituent of numerous plant subspecies including wheat, tomato and sweet corn. 1-(Malonylamino)cyclopropanecarboxylic acid is found in cereals and cereal products and garden tomato.
(1R,4R,5S,6R)-4-Amino-2-oxabicyclo[3.1.0]hexane-4,6-dicarboxylic acid
1-(2-Hydroxyethyl-2-hydroxymethyl)-5-nitro-imidazole
1h-[1,2,4]Oxadiazolo[4,3-a]quinoxalin-1-one
D004791 - Enzyme Inhibitors
1-(2-Hydroxyethyl)-2-hydroxymethyl-5-nitroimidazole
6-Fluoropyridoxol
C8H10FNO3 (187.06446820000002)
alpha-Monofluoromethyl histidine
C7H10FN3O2 (187.07570120000003)
Fluoromethylhistidine
C7H10FN3O2 (187.07570120000003)
Makaluvamine I
D000970 - Antineoplastic Agents > D059003 - Topoisomerase Inhibitors > D059005 - Topoisomerase II Inhibitors D004791 - Enzyme Inhibitors
metamitron-desamino
A member of the class of 1,2,4-triazines that is metamitron in which the amino group has been replaced by a hydrogen atom. It is a metabolite of metamitron. CONFIDENCE standard compound; EAWAG_UCHEM_ID 4 EAWAG_UCHEM_ID 4; CONFIDENCE standard compound CONFIDENCE standard compound; INTERNAL_ID 2064
9,9a-dihydro-naphtho[2,3-c]isoxazol-3(1H)-one|naphthisoxazol A
1-Acetylindole-3-carboxaldehyde
An N-acylindole that is N-acetylindole carrying an additional formyl substituent at position 3.
4-Methyl-[1,2]naphthochinon-2-oxim|4-methyl-[1,2]naphthoquinone-2-oxime
Metamitron desamino
CONFIDENCE Reference Standard (Level 1); INTERNAL_ID 82
p-Toluidine-m-sulfonic acid
ORIGINAL_ACQUISITION_NO 1617; CONFIDENCE standard compound; INTERNAL_ID 791; DATASET 20200303_ENTACT_RP_MIX508; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_PRECURSOR_SCAN_NO 1616 CONFIDENCE standard compound; INTERNAL_ID 791; DATASET 20200303_ENTACT_RP_MIX508; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 1617; ORIGINAL_PRECURSOR_SCAN_NO 1616 CONFIDENCE standard compound; INTERNAL_ID 791; DATASET 20200303_ENTACT_RP_MIX508; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 1611; ORIGINAL_PRECURSOR_SCAN_NO 1610 CONFIDENCE standard compound; INTERNAL_ID 791; DATASET 20200303_ENTACT_RP_MIX508; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 1616; ORIGINAL_PRECURSOR_SCAN_NO 1615 CONFIDENCE standard compound; INTERNAL_ID 791; DATASET 20200303_ENTACT_RP_MIX508; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 1612; ORIGINAL_PRECURSOR_SCAN_NO 1611
2,5-Dimethoxy-4-chloroaniline
CONFIDENCE standard compound; INTERNAL_ID 945; DATASET 20200303_ENTACT_RP_MIX500; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 7030; ORIGINAL_PRECURSOR_SCAN_NO 7028 CONFIDENCE standard compound; INTERNAL_ID 945; DATASET 20200303_ENTACT_RP_MIX500; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 7022; ORIGINAL_PRECURSOR_SCAN_NO 7018 CONFIDENCE standard compound; INTERNAL_ID 945; DATASET 20200303_ENTACT_RP_MIX500; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 7034; ORIGINAL_PRECURSOR_SCAN_NO 7032 CONFIDENCE standard compound; INTERNAL_ID 945; DATASET 20200303_ENTACT_RP_MIX500; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 7049; ORIGINAL_PRECURSOR_SCAN_NO 7046 CONFIDENCE standard compound; INTERNAL_ID 945; DATASET 20200303_ENTACT_RP_MIX500; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 7069; ORIGINAL_PRECURSOR_SCAN_NO 7066
4-Fluoro-4-aminodiphenyl
CONFIDENCE standard compound; INTERNAL_ID 1012; DATASET 20200303_ENTACT_RP_MIX508; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 7728; ORIGINAL_PRECURSOR_SCAN_NO 7723 CONFIDENCE standard compound; INTERNAL_ID 1012; DATASET 20200303_ENTACT_RP_MIX508; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 7766; ORIGINAL_PRECURSOR_SCAN_NO 7763
p-Toluidine-o-sulfonic acid
CONFIDENCE standard compound; INTERNAL_ID 1329; DATASET 20200303_ENTACT_RP_MIX508; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 1617; ORIGINAL_PRECURSOR_SCAN_NO 1616 CONFIDENCE standard compound; INTERNAL_ID 1329; DATASET 20200303_ENTACT_RP_MIX508; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 1611; ORIGINAL_PRECURSOR_SCAN_NO 1610 CONFIDENCE standard compound; INTERNAL_ID 1329; DATASET 20200303_ENTACT_RP_MIX508; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 1616; ORIGINAL_PRECURSOR_SCAN_NO 1615 CONFIDENCE standard compound; INTERNAL_ID 1329; DATASET 20200303_ENTACT_RP_MIX508; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 1612; ORIGINAL_PRECURSOR_SCAN_NO 1611 CONFIDENCE standard compound; INTERNAL_ID 1329; DATASET 20200303_ENTACT_RP_MIX504; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 9107; ORIGINAL_PRECURSOR_SCAN_NO 9103 CONFIDENCE standard compound; INTERNAL_ID 1329; DATASET 20200303_ENTACT_RP_MIX504; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 9120; ORIGINAL_PRECURSOR_SCAN_NO 9117
3-Indoleacrylic acid [M+H-H2O]+; AIF: CE10; MS2Dec
3-Indoleacrylic acid [M+H-H2O]+; AIF: CE30; MS2Dec
1-(2-Hydroxyethyl)-2-hydroxymethyl-5-nitroimidazole
3-Hydrazinylpiperidine dihydrochloride
C5H15Cl2N3 (187.06429699999998)
2,4-Dioxo-1,2,3,4-tetrahydroquinazoline-7-carbonitrile
Pyrimido[1,2-a]benzimidazol-2(1H)-one, 3,4-dihydro- (8CI,9CI)
1H-Imidazole-4-carboxylicacid,2-methoxy-5-nitro-(9CI)
L-Glutamic acid monosodium salt monohydrate
C5H10NNaO5 (187.04566499999999)
D000074385 - Food Ingredients > D005503 - Food Additives D010592 - Pharmaceutic Aids > D005421 - Flavoring Agents
8-Methyl-2-Oxo-1,2-Dihydro-Quinoline-3-Carbaldehyde
3-Aminomethylphenylboronic acid hydrochloride
C7H11BClNO2 (187.05713260000002)
Cyclopropanamine, 1-(4-fluorophenyl)-, hydrochloride
C9H11ClFN (187.05640079999998)
2-amino-5-(trifluoromethyl)pyridine-3-carbonitrile
6-Fluoro-1,2,3,4-tetrahydro-isoquinoline hydrochloride
C9H11ClFN (187.05640079999998)
Hydrazinecarboxamide,N-phenyl-, hydrochloride (1:1)
1H-Imidazole-4-carboxylicacid,2-amino-4,5-dihydro-4-hydroxy-5-oxo-,ethyl
ethyl 5-amino-2-sulfanylidene-1,3-dihydroimidazole-4-carboxylate
C6H9N3O2S (187.04154540000002)
5-Fluoro-1,2,3,4-tetrahydro-isoquinoline hydrochloride
C9H11ClFN (187.05640079999998)
6-fluoro-2,3-dihydro-1H-inden-1-amine,hydrochloride
C9H11ClFN (187.05640079999998)
7-Fluoro-1,2,3,4-tetrahydro-isoquinoline hydrochloride
C9H11ClFN (187.05640079999998)
Pyrido[4,3:4,5]pyrrolo[1,2-a]pyrazin-1(2H)-one, 3,4-dihydro- (9CI)
2-[(6-chloro-2-methyl-4-pyrimidinyl)amino]-1-ethanol
5-CHLOROMETHYL-3-HYDROXY-4-HYDROXYMETHYL-2-METHYLPYRIDINE
3-(methylamino)pyridine-2-sulfonamide
C6H9N3O2S (187.04154540000002)
2-chloro-5,6,7,8-tetrahydro-4H-thieno[2,3-d]azepine
3-chloro-5,6,7,8-tetrahydro-4H-thieno[2,3-d]azepine
N-(2-Chloro-6-fluorobenzyl)ethanamine
C9H11ClFN (187.05640079999998)
1,2,3,6-TETRAHYDRO-4-(TRIFLUOROMETHYL)PYRIDINE HYDROCHLORIDE
C6H9ClF3N (187.03755800000002)
6-(CHLOROMETHYL)-N,N-DIMETHYL-1,3,5-TRIAZINE-2,4-DIAMINE
C6H10ClN5 (187.06246900000002)
trimethyl-(1,1,2,2-tetradeuterio-2-hydroxyethyl)azanium,bromide
C5H10BrD4NO (187.05097811199997)
2-chloro-N-(3,5-dimethyl-1H-pyrazol-4-yl)acetamide
(2Z)-3-Thiomorpholinylideneacetic acid ethyl ester
4-morpholino-1,2,5-thiadiazol-3-ol
C6H9N3O2S (187.04154540000002)
4-Aminomethylphenylboronicacidhydrochloride
C7H11BClNO2 (187.05713260000002)
(3-AMINO-4-METHYLPHENYL)BORONIC ACID HYDROCHLORIDE
C7H11BClNO2 (187.05713260000002)
1-(3-Fluorphenyl)cyclopropanaminhydrochlorid(1:1)
C9H11ClFN (187.05640079999998)
Desmethylmisonidazole
C274 - Antineoplastic Agent > C798 - Radiosensitizing Agent D011838 - Radiation-Sensitizing Agents D009676 - Noxae > D009153 - Mutagens
1,2-Dihydro-7-Methyl-2-Oxo-3-Quinolinecarboxaldehyde
2-CHLORO-1-(1-ISOPROPYL-1H-1,2,4-TRIAZOL-5-YL)ETHANONE
2,4-dimethylpyridine-3-carboxylic acid,hydrochloride
1H-Pyrazole-3-carboxylicacid,5-methoxy-4-nitro-(9CI)
3-Isoxazolecarbonyl chloride, 5-(2-methylpropyl)- (9CI)
4-Cyano-1H-pyrrolo[2,3-b]pyridine-3-carboxylic acid
6-Cyano-1H-pyrrolo[3,2-b]pyridine-3-carboxylic acid
2-(2-BENZOTHIAZOLYL)-6-METHYLPHENOL
C7H11BClNO2 (187.05713260000002)
5-FLUORO-1,2,3,4-TETRAHYDRO-QUINOLINE HYDROCHLORIDE
C9H11ClFN (187.05640079999998)
(S)-(-)-(3-CHLORO-2-HYDROXYPROPYL)TRIMETHYLAMMONIUM CHLORIDE
C6H15Cl2NO (187.05306399999998)
1-METHYL-2-OXO-1,2-DIHYDROQUINOLINE-3-CARBALDEHYDE
1H-Pyrrolo[2,3-b]pyridine-2-carboxylic acid, 3-cyano-
4-Oxazolecarbonyl chloride, 2-(1,1-dimethylethyl)- (9CI)
DL-Norephedrine hydrochloride
D018373 - Peripheral Nervous System Agents > D001337 - Autonomic Agents > D013566 - Sympathomimetics C78272 - Agent Affecting Nervous System > C29747 - Adrenergic Agent > C87053 - Adrenergic Agonist D018377 - Neurotransmitter Agents > D018663 - Adrenergic Agents > D000322 - Adrenergic Agonists D019141 - Respiratory System Agents > D014663 - Nasal Decongestants D002317 - Cardiovascular Agents > D014662 - Vasoconstrictor Agents D019440 - Anti-Obesity Agents > D001067 - Appetite Depressants
5,6,7,8-Tetrahydropyrido[3,4-d]pyrimidin-4(3H)-one hydrochloride
6-Methyl-2-oxo-1,2-dihydroquinoline-3-carbaldehyde
Histamineα,α,β,β-d4 dihydrochloride
C5H7Cl2D4N3 (187.05810731199998)
3-Chloro-2-hydroxypropyltrimethylammonium chloride
C6H15Cl2NO (187.05306399999998)
(1R,2S)-2-(4-fluorophenyl)cyclopropan-1-amine hydrochloride
C9H11ClFN (187.05640079999998)
2-(3-fluorophenyl)cyclopropanamine hydrochloride
C9H11ClFN (187.05640079999998)
4-Hydroxy-2-methylthiazole-5-carboxylic acid ethyl ester
4-Isoxazolecarbonyl chloride, 3-methyl-5-(1-methylethyl)- (9CI)
5,6,7,8-tetrahydropyrido[3,4-d]pyrimidin-4(4aH)-one hydrochloride
2,4-DIOXO-1,2,3,4-TETRAHYDROQUINAZOLINE-8-CARBONITRILE
(S)-1-[3,5-BIS(TRIFLUOROMETHYL)PHENYL]ETHYLAMINEHCL
8-FLUORO-1,2,3,4-TETRAHYDROISOQUINOLINE HCL
C9H11ClFN (187.05640079999998)
Cathine hydrochloride
D019440 - Anti-Obesity Agents > D001067 - Appetite Depressants
alpha-Fluoromethylhistidine
C7H10FN3O2 (187.07570120000003)
D018373 - Peripheral Nervous System Agents > D001337 - Autonomic Agents D005765 - Gastrointestinal Agents > D000932 - Antiemetics D002491 - Central Nervous System Agents D004791 - Enzyme Inhibitors
alpha-Monofluoromethylhistidine
C7H10FN3O2 (187.07570120000003)
D018373 - Peripheral Nervous System Agents > D001337 - Autonomic Agents D005765 - Gastrointestinal Agents > D000932 - Antiemetics D002491 - Central Nervous System Agents D004791 - Enzyme Inhibitors
(1R,4R,5S,6R)-4-Amino-2-oxabicyclo[3.1.0]hexane-4,6-dicarboxylic acid
LY379268 is a potent, selective and brain-penetrant mGlu2/3R agonist with EC50 values of 2.69 nM (mGlu2) and 4.48 nM (mGlu3). LY379268 has no activity on human mGlu 1a, 4a, 5a or 7a receptors. LY379268 has antioxidant and neuroprotective effects[1][2].
(3-methyl-2-oxo-2,3-dihydro-1H-benzimidazol-1-yl)acetonitrile
1-Hydroxy-2-naphthoate
A hydroxy monocarboxylic acid anion that is the conjugate base of 1-hydroxy-2-naphthoic acid.
(2S)-2-azaniumyl-3-(4-sulfanyl-1H-imidazol-5-yl)propanoate
C6H9N3O2S (187.04154540000002)
N-acetyl-D-glutaminate
The conjugate base of N(2)-acetyl-D-glutamine; major species at pH 7.3.
(2E)-2-[[formyl(methyl)amino]methylidene]butanedioic acid
Deethylatrazine
C6H10ClN5 (187.06246900000002)
A chloro-1,3,5-triazine that is 6-chloro-1,3,5-triazine-2,4-diamine in which one of the hydrogens of the amino group is replaced by a propan-2-yl group.
(2S,4S)-4-hydroxy-2,3,4,5-tetrahydropyridine-2,6-dicarboxylic acid
N-acetyl-L-glutamate(2-)
An N-acyl-L-alpha-amino acid anion resulting from deprotonation of both carboxy groups of N-acetyl-L-glutamic acid.
N-acetyl-L-glutaminate
An N(2)-acetylglutaminate that has L-configuration; major species at pH 7.3.