4271-30-1

Basic information

• Product Name: N-(4-Aminobenzoyl)-L-glutamic acid
• Synonyms: H-4-ABZ-GLU-OH;4-AMINOBENZOYLGLUTAMIC ACID;4-AMINOBENZOIC GLUTAMIC ACID;N-(P-AMINOBENZOYL)-L-GLUTAMIC ACID;P-AMINOBENZOYL-L-GLUTAMIC ACID;P-AMINO BENZAMIDE GLUTAMIC ACID;N-(4-AMINOBENZOYL)-L-GLUTAMIC ACID;4-aminobenzoyl－L-glutamic acid
• CAS NO: 4271-30-1
• Molecular Formula: C₁₂H₁₄N₂O₅
• Molecular Weight: 266.25
• EINECS: 224-261-7
• Product Categories: Amino Acids;A - HPeptide Synthesis;Amino Acid Derivatives;Amino Acids;Glutamic Acid;Modified Amino Acids;Amino Acids & Derivatives;Metabolites & Impurities;amino;Intermediate
• Mol File: 4271-30-1.mol
• Article Data: 13

Chemical Properties

• Melting Point: ~175 °C (dec.)
• Boiling Point: 409.45°C (rough estimate)
• Flash Point: 320.9 °C
• Appearance: /
• Density: 1.2846 (rough estimate)
• Vapor Pressure: 1.37E-15mmHg at 25°C
• Refractive Index: 1.6660 (estimate)
• Storage Temp.: −20°C
• Solubility: Aqueous Base (Sparingly), Aqueous Acid (Sparingly), DMSO (Sparingly), Methanol (
• PKA: 3.50±0.10(Predicted)
• Stability: Hygroscopic
• Merck: 14,426
• BRN: 2816320
• CAS DataBase Reference: N-(4-Aminobenzoyl)-L-glutamic acid(CAS DataBase Reference)
• NIST Chemistry Reference: N-(4-Aminobenzoyl)-L-glutamic acid(4271-30-1)
• EPA Substance Registry System: N-(4-Aminobenzoyl)-L-glutamic acid(4271-30-1)

Safety Data

• Statements: 36/37/38
• Safety Statements: 26-36/37/39
• WGK Germany: 3
• Hazardous Substances Data: 4271-30-1(Hazardous Substances Data)

Usage

Chemical Properties

Light Tan Waxy Solid

Uses

Different sources of media describe the Uses of 4271-30-1 differently. You can refer to the following data:
1. Marker in folate metabolism studies.
2. Major metabolite of 5-Methyltetrahydrofolic Acid

Definition

ChEBI: A dipeptide resulting from the formal condensation of the carboxylic acid group of 4-aminobenzoic acid with the amino group of L-glutamic acid.

Purification Methods

Crystallise the acid from H2O. Also purify it by dissolving 2.7g in H2O (130mL), adding aqueous NaOH to pH 5.5 and adding portionwise a solution of 0.5M CuSO4 to complete precipitation of the Cu salt. This salt is filtered off, suspended in H2O and H2S is bubbled through to precipitate CuS, filter, evaporate and recrystallise the residue from H2O. It has max (H2O) at 273nm. [Backer & Houtman Recl Trav Chim Pays-Bas 70 738, 743 1951, Beilstein 14 IV 1153.]

InChI:InChI=1/C12H14N2O5/c13-8-3-1-7(2-4-8)11(17)14-9(12(18)19)5-6-10(15)16/h1-4,9H,5-6,13H2,(H,14,17)(H,15,16)(H,18,19)/t9-/m1/s1

Synthetic route

Di-tert-butyl 3-fluoro,4-nitrobenzoyl-L-glutamate → N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1)

Conditions	Yield
With ammonium formate; palladium-carbon In methanol	99%

p-Nitrobenzoyl-L-(+)-glutamic acid (6758-40-3) → N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1)

Conditions	Yield
With palladium 10% on activated carbon; ammonium formate In methanol at 20℃; for 0.5h; Time; Concentration;	96.58%
With palladium on carbon; hydrazine hydrate In ethanol at 80℃; for 2.5h;	78%
With ethanol; palladium Hydrogenation;

dimethyl p-trifluoroacetamidobenzoyl-L-glutamate (233600-78-7) → N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1)

Conditions	Yield
With sodium hydroxide; water In methanol at 23℃; for 4h;	61%

diethyl N-(p-aminobenzoyl)-L-glutamate (13726-52-8) → N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1)

(S)-2-(4-(((2-amino-4-hydroxypteridin-6-yl)methyl)amino)benzamido)pentanedioic acid (59-30-3) → N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1) + 4-amino-benzoic acid (150-13-0) + pterin-6-carboxylic acid (948-60-7) + 6-pterinaldehyde (712-30-1)

Conditions	Yield
With hydroxide In water Product distribution;

(S)-2-(4-(((2-amino-4-hydroxypteridin-6-yl)methyl)amino)benzamido)pentanedioic acid (59-30-3) → N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1) + pterin-6-carboxylic acid (948-60-7) + 6-pterinaldehyde (712-30-1)

Conditions	Yield
With phosphate-buffered saline pH=7.4; UV-irradiation;

N-[4-[[(2-amino-1,4,5,6,7,8-hexahydro-5-methyl-4-oxo-6-pteridinyl)methyl]amino]benzoyl]-L-glutamic acid → C20H23N7O6 + N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1)

Conditions	Yield
In phosphate buffer at 25 - 30℃; pH=7.4; Kinetics; UV-irradiation;

folic acid (59-30-3) → 6-formylpterin (712-30-1) + N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1)

Conditions	Yield
With oxygen; rose bengal In water-d2 pH=10.5; Kinetics; Irradiation;

L-glutamic acid (56-86-0) → N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1)

Conditions	Yield
Multi-step reaction with 3 steps 1: 79 percent / SOCl2 / 18 h / Ambient temperature 2: 70 percent / HOBt, DCC, DIEA / tetrahydrofuran / 48 h / -5 °C 3: 61 percent / NaOH, H2O / methanol / 4 h / 23 °C View Scheme
Multi-step reaction with 2 steps 1: aq. NaOH solution 2: palladium; ethanol / Hydrogenation View Scheme

4-(trifluoroacetamido)benzoic acid (404-26-2) → N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1)

Conditions	Yield
Multi-step reaction with 2 steps 1: 70 percent / HOBt, DCC, DIEA / tetrahydrofuran / 48 h / -5 °C 2: 61 percent / NaOH, H2O / methanol / 4 h / 23 °C View Scheme

2,2,2-trifluoro-N-(4-iodophenyl)acetamide (126063-08-9) → N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1)

Conditions	Yield
Multi-step reaction with 3 steps 1: 1.) n-BuLi / 1.) ether, hexane, -78 deg C, 2 h, 2.) ether, hexane, -78 deg C to r.t. 2: 70 percent / HOBt, DCC, DIEA / tetrahydrofuran / 48 h / -5 °C 3: 61 percent / NaOH, H2O / methanol / 4 h / 23 °C View Scheme

L-glutamic dimethyl ester hydrochloride (23150-65-4) → N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1)

Conditions	Yield
Multi-step reaction with 2 steps 1: 70 percent / HOBt, DCC, DIEA / tetrahydrofuran / 48 h / -5 °C 2: 61 percent / NaOH, H2O / methanol / 4 h / 23 °C View Scheme

p-aminoiodobenzene (540-37-4) + p-chloro-benzenesulfonyl chloride → N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1)

Conditions	Yield
Multi-step reaction with 4 steps 1: 78 percent / CH2Cl2 / 1 h / Ambient temperature 2: 1.) n-BuLi / 1.) ether, hexane, -78 deg C, 2 h, 2.) ether, hexane, -78 deg C to r.t. 3: 70 percent / HOBt, DCC, DIEA / tetrahydrofuran / 48 h / -5 °C 4: 61 percent / NaOH, H2O / methanol / 4 h / 23 °C View Scheme

diethyl (4-nitrobenzoyl)-L-glutamate (7148-24-5) → N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1)

Conditions	Yield
Multi-step reaction with 2 steps 1: aqueous hydrochloric acid 2: palladium; ethanol / Hydrogenation View Scheme

4-nitro-benzoyl chloride (122-04-3) → N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1)

Conditions	Yield
Multi-step reaction with 3 steps 1: benzene 2: aqueous hydrochloric acid 3: palladium; ethanol / Hydrogenation View Scheme
Multi-step reaction with 2 steps 1: benzene; calcium oxide / <40 2: aqueous ammonium sulfide View Scheme

4-nitro-benzoic acid (62-23-7) → N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1)

Conditions	Yield
Multi-step reaction with 3 steps 1: N,N-dimethyl-formamide; bis(trichloromethyl) carbonate / 1 h / 40 °C 2: sodium hydroxide / water / 1 h / 0 - 20 °C / pH 8 3: palladium 10% on activated carbon; ammonium formate / methanol / 0.5 h / 20 °C View Scheme
Multi-step reaction with 3 steps 1.1: oxalyl dichloride / tetrahydrofuran; N,N-dimethyl-formamide / 55 °C 2.1: sodium hydroxide / water 2.2: 5 °C / pH 8 3.1: iron(III) chloride hexahydrate; hydrazine hydrate / methanol / 20 °C View Scheme

folate (59-30-3) → N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1)

Conditions	Yield
In water UV-irradiation;

folate (59-30-3) → 6-formylpterin (712-30-1) + N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1)

Conditions	Yield
With Pt(Py)2(N3)2(OH)2 In dimethylsulfoxide-d6; water-d2 at 37℃; for 2h; Irradiation;

N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1) + 2-amino-4-hydroxy-6-bromomethylpteridine (89794-15-0) → (S)-2-(4-(((2-amino-4-hydroxypteridin-6-yl)methyl)amino)benzamido)pentanedioic acid (59-30-3)

Conditions	Yield
In N,N-dimethyl acetamide at 45℃; for 4h; Concentration; Temperature; Solvent; Industrial scale;	89%

N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1) + 2-amino-4-hydroxy-6-chloromethylpteridine → (S)-2-(4-(((2-amino-4-hydroxypteridin-6-yl)methyl)amino)benzamido)pentanedioic acid (59-30-3)

Conditions	Yield
In methanol at 45℃; for 5h; Concentration; Temperature; Solvent; Industrial scale;	85%

N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1) + 2,5,6-triamino-1,4-dihydropyrimidin-4-one hydrochloride → folate (59-30-3)

Conditions	Yield
With 1,1,1-trichloroacetone; sodium sulfite In water at 40 - 50℃; for 1h; pH=3 - 4; pH-value; Temperature;	85%

1,1,3-trichloroacetone (921-03-9) + N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1) + 2,4,5-triamino-6-hydroxypyrimidine sulfate (35011-47-3) → folate (59-30-3)

Conditions	Yield
With sodium metabisulfite at 20 - 30℃; for 2h; Temperature; Ionic liquid;	83.2%
With sodium metabisulfite; sodium acetate at 45℃; for 3h; Temperature;	46.2%

N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1) + 2-amino-6-(bromomethyl)-4(1H)-pteridinone hydrobromide (59212-10-1) → folic acid (59-30-3)

Conditions	Yield
In N,N-dimethyl acetamide 1.) 22-25 deg C, 96 h; 2.) 50-60 deg C, 30 min; 3.) 22-25 deg C, 24 h;	80%

1,1,3-trichloroacetone (921-03-9) + N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1) + 2,4,5-triamino-6-hydroxypyrimidine sulfate (35011-47-3) → (S)-2-(4-(((2-amino-4-hydroxypteridin-6-yl)methyl)amino)benzamido)pentanedioic acid (59-30-3)

Conditions	Yield
With sodium hydroxide at 55℃; for 9h; pH=3;	80%
Stage #1: 1,1,3-trichloroacetone; 2,4,5-triamino-6-hydroxypyrimidine sulfate With sodium metabisulfite In methanol; water for 0.5h; Large scale; Stage #2: N-(4-aminobenzoyl)-L-glutamic acid With sodium hydroxide In methanol; water at 40 - 45℃; for 6h; pH=3 - 3.5; Solvent; Large scale;	69.7%

1,1,1-trichloroacetone (918-00-3) + N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1) + 2,4,5-triamino-6-hydroxypyrimidine sulfate (35011-47-3) → folate (59-30-3)

Conditions	Yield
Stage #1: 1,1,1-trichloroacetone; N-(4-aminobenzoyl)-L-glutamic acid With sodium acetate; sodium sulfite In acetic acid at 43℃; for 0.5h; Stage #2: 2,4,5-triamino-6-hydroxypyrimidine sulfate In acetic acid at 38℃; for 5h;	75.5%

6-bromomethyl-pteridine-2,4-diamine (59368-16-0) + N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1) → aminopterin (54-62-6)

Conditions	Yield
In dimethylacetamide (DMAC) at 25℃; for 2h;	68%
In ISOPROPYLAMIDE at 25℃; for 18h;	68%

N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1) + water (7732-18-5) + 6-bromomethyl-2,4-diaminopteridine hydrobromide (52853-40-4) → aminopterin (54-62-6)

Conditions	Yield
In ethanol	68%

N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1) + <7-15N>guanide (128844-61-1) + [3-(13)C]-D-glucose → [5-15N][6-13C]-7,8-dihydrofolic acid

Conditions

Yield

Stage #1: [3-(13)C]-D-glucose With cysteine disulfide; pyruvate kinase from rabbit muscle; glutaredoxin 2; glucose-6-phosphate dehydrogenase from L. mesenteroides; glutathione reductase from baker’s yeast; hexokinase type F-300 from S. cerevisiae; myokinase from rabbit muscle; phosphoriboisomerase type I from spinach; potassium chloride; NADP; phospho(enol)pyruvic acid mono potassium salt; ATP; magnesium chloride In aq. buffer at 37℃; pH=7; Glovebox; Inert atmosphere; Enzymatic reaction; Stage #2: With guanylate kinase; ribose-phosphate pyrophosphokinase; xanthine guanine phosphoribosyl transferase In aq. buffer for 0.25h; Glovebox; Inert atmosphere; Enzymatic reaction; Stage #3: N-(4-aminobenzoyl)-L-glutamic acid; <7-15N>guanide Further stages;

30%

D-Glucose (2280-44-6) + 2-amino-1,9-dihydro-6H-purin-6-one (73-40-5) + N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1) → (S)-2-{4-[(2-Amino-4-oxo-3,4,7,8-tetrahydro-pteridin-6-ylmethyl)-amino]-benzoylamino}-pentanedioic acid (4033-27-6)

Conditions

Yield

Stage #1: D-Glucose With cysteine disulfide; pyruvate kinase from rabbit muscle; glutaredoxin 2; glucose-6-phosphate dehydrogenase from L. mesenteroides; glutathione reductase from baker’s yeast; hexokinase type F-300 from S. cerevisiae; myokinase from rabbit muscle; phosphoriboisomerase type I from spinach; NADP; phospho(enol)pyruvic acid mono potassium salt; ATP In aq. buffer at 37℃; pH=7; Glovebox; Inert atmosphere; Enzymatic reaction; Stage #2: With guanylate kinase; ribose-phosphate pyrophosphokinase; xanthine guanine phosphoribosyl transferase In aq. buffer for 0.25h; Glovebox; Inert atmosphere; Enzymatic reaction; Stage #3: 2-amino-1,9-dihydro-6H-purin-6-one; N-(4-aminobenzoyl)-L-glutamic acid Further stages;

30%

N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1) + 2-amino-O4-benzyl-6-formylpteridine (737817-22-0) → O4-benzylfolic acid

Conditions	Yield
With sodium cyanoborohydride In N,N-dimethyl-formamide for 0.0833333h;	17.7%
Stage #1: N-(4-aminobenzoyl)-L-glutamic acid; 2-amino-O4-benzyl-6-formylpteridine In DMF (N,N-dimethyl-formamide) Stage #2: With sodium cyanoborohydride; acetic acid In DMF (N,N-dimethyl-formamide) for 0.0833333h;	17.7%

2,5,6-triamino-3,4-dihydro-4-pyrimidinone (1004-75-7) + N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1) + <1,1,3-13C2> trichloroacetone → <7,9-13C2> folic acid

Conditions	Yield
With sodium hydrogencarbonate; sodium hydrogensulfite; <1,3-13C2> dichloroacetone In ethanol for 72h; pH 4.0;	10%

methanol (67-56-1) + N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1) → dimethyl N-(4-amino-benzoyl)-L-glutamate (52407-60-0)

Conditions	Yield
With acetyl chloride

4-chloroquinazoline (5190-68-1) + N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1) → N-(4-quinazolin-4-ylamino-benzoyl)-L-glutamic acid

Conditions	Yield
With ethanol

formic acid (64-18-6) + N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1) → N-(4-formylamino-benzoyl)-L-glutamic acid (93528-16-6)

4,5,6-triamino-1H-pyrimidine-2-thione (1073-99-0) + 2,3-dibromopropanal (5221-17-0) + N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1) → N-{4-[(4-amino-2-thioxo-1,2-dihydro-pteridin-6-ylmethyl)-amino]-benzoyl}-L-glutamic acid (103207-69-8)

5,6-diaminouracil (3240-72-0) + 2,3-dibromopropanal (5221-17-0) + N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1) → N-{4-[(2,4-dioxo-1,2,3,4-tetrahydro-pteridin-6-ylmethyl)-amino]-benzoyl}-L-glutamic acid (25663-25-6)

Conditions	Yield
With sodium acetate; acetic acid

5,6-diaminouracil (3240-72-0) + 1,1,3-tribromoacetone (3475-39-6) + N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1) → N-{4-[(2,4-dioxo-1,2,3,4-tetrahydro-pteridin-6-ylmethyl)-amino]-benzoyl}-L-glutamic acid (25663-25-6)

Conditions	Yield
With aqueous solution of pH 1-5

2,5,6-triamino-3,4-dihydro-4-pyrimidinone (1004-75-7) + 1,1,3-trichloroacetone (921-03-9) + N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1) → folic acid (59-30-3)

2,5,6-triamino-3,4-dihydro-4-pyrimidinone (1004-75-7) + 1,1,3-tribromoacetone (3475-39-6) + N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1) → folic acid (59-30-3)

2,5,6-triamino-3,4-dihydro-4-pyrimidinone (1004-75-7) + 2,2,3-tribromopropanal (26944-17-2) + N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1) → folic acid (59-30-3)

2,5,6-triamino-3,4-dihydro-4-pyrimidinone (1004-75-7) + N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1) → N-((Ξ)-9-methyl-pteroyl)-L-glutamic acid (2179-16-0)

Conditions	Yield
With 2,2,3-trichlorobutyraldehyde

3-phthalimidopropionyl chloride (17137-11-0) + N-(4-aminobenzoyl)-L-glutamic acid (4271-30-1) → N-{4-[(N,N-phthaloyl-β-alanyl)-amino]-benzoyl}-L-glutamic acid

Conditions	Yield
With 1,4-dioxane; water; magnesium oxide

Upstream product

• 62-23-7 4-nitro-benzoic acid 
• 59-30-3 folate 
• 122-04-3 4-nitro-benzoyl chloride 
• 7148-24-5 diethyl (4-nitrobenzoyl)-L-glutamate 
• 540-37-4 p-aminoiodobenzene 
• 23150-65-4 L-glutamic dimethyl ester hydrochloride 
• 126063-08-9 2,2,2-trifluoro-N-(4-iodophenyl)acetamide 
• 404-26-2 4-(trifluoroacetamido)benzoic acid 
• 56-86-0 L-glutamic acid 
• 59-30-3 folic acid 
• 76937-22-9 N-[4-[[(2-amino-1,4,5,6,7,8-hexahydro-5-methyl-4-oxo-6-pteridinyl)methyl]amino]benzoyl]-L-glutamic acid 
• 59-30-3 (S)-2-(4-(((2-amino-4-hydroxypteridin-6-yl)methyl)amino)benzamido)pentanedioic acid 
• 233600-78-7 dimethyl p-trifluoroacetamidobenzoyl-L-glutamate 
• 13726-52-8 diethyl N-(p-aminobenzoyl)-L-glutamate 

Downstream Products

• 6190-83-6 N-{4-[(2-amino-4,7-dioxo-3,4,7,8-tetrahydro-pteridin-6-ylmethyl)-amino]-benzoyl}-L-glutamic acid 
• 23961-18-4 N-(4-glycylamino-benzoyl)-L-glutamic acid 
• 133465-68-6 (S)-2-[4-(2-Amino-6-oxo-6,9-dihydro-1H-purin-8-ylazo)-benzoylamino]-pentanedioic acid 
• 131619-68-6 N-<4-<<(4-amino-1-methyl-2,2-dioxopyrazino<2,3-c>-1,2,6-thiadiazin-7-yl)methyl>amino>benzoyl>-L-glutamic acid 
• 131619-67-5 N-<4-<<(4-amino-1-benzyl-2,2-dioxopyrazino<2,3-c>-1,2,6-thiadiazin-7-yl)methyl>amino>benzoyl>-L-glutamic acid 
• 59-30-3 folic acid 
• 142811-49-2 N-<4-<<2(R)--3-<(2-amino-5-nitro-4(3H)-oxopyrimidin-6-yl)amino>propyl>amino>benzoyl>-L-glutamic acid 
• 78711-39-4 (S)-2-{4-[(2-Acetylamino-4-oxo-3,4-dihydro-pyrido[3,2-d]pyrimidin-6-ylmethyl)-amino]-benzoylamino}-pentanedioic acid 
• 122712-56-5 N-(2'-ethoxycarbonylamino-4'-amino-azobenzene-4-carbonyl)-L-glutamic acid 
• 94961-89-4 5,8-dideaza-5,6,7,8-tetrahydrofolic acid 
• 95943-67-2 2,4-bisacetamido-5,8-dideaza-5,6,7,8-tetrahydroaminopterin 
• 4033-27-6 (S)-2-{4-[(2-Amino-4-oxo-3,4,7,8-tetrahydro-pteridin-6-ylmethyl)-amino]-benzoylamino}-pentanedioic acid 
• 54-62-6 aminopterin 
• 103508-85-6 N-{4-[(2-amino-4-dimethylamino-pteridin-6-ylmethyl)-amino]-benzoyl}-L-glutamic acid 

Relevant articles and documents

Reactivity of conjugated and unconjugated pterins with singlet oxygen (O2(1Δg)): Physical quenching and chemical reaction

Pterins (PTs) belong to a class of heterocyclic compounds present in a wide range of living systems. They participate in relevant biological functions and are involved in different photobiological processes. We have investigated the reactivity of conjugated PTs (folic acid [FA], 10-methylfolic acid [MFA], pteroic acid [PA]) and unconjugated PTs (PT, 6-hydroxymethylpterin [HPT], 6-methylpterin [MPT], 6,7-dimethylpterin [DPT], rhamnopterin [RPT]) with singlet oxygen (1O2) in aqueous solutions, and compared the efficiencies of chemical reaction and physical quenching. The chemical reactions between 1O2, produced by photosensitization, and PT derivatives were followed by UV-visible spectrophotometry and high-performance liquid chromatography, and corresponding rate constants (kr) were evaluated. Whenever possible, products were identified and quantified. Rate constants of 1O2 total quenching by the PT derivatives investigated were obtained from steady-state 1O2 luminescence measurements. Results show that the behavior of conjugated PTs differs considerably from that of unconjugated derivatives, and the mechanisms of 1O2 physical quenching by these compounds and of their chemical reaction with 1O2 are discussed in relation to their structural features.

Unexpected photoactivation pathways in a folate-receptor-targetedtrans-diazido Pt(iv) anticancer pro-drug

A conjugate between a photoactivetrans-diazido Pt(iv) pro-drug,trans,trans,trans-[Pt(N3)2(OH)2(py)2], and folic acid has been synthesized and fully characterized by high resolution ESI-MS, NMR and UV-vis spectroscopy. Photoactivation of the Pt-folate conjugate with visible light confirmed the generation of cytotoxic Pt(ii) species capable of binding to guanine nucleobases. Importantly, photoreduction of the Pt(iv) complex triggered the photodecomposition of the folate vector into ap-aminobenzoate-containing fragment and several pterin derivatives, including 6-formylpterin. Besides exhibiting high dark stability in physiological-like conditions, the Pt-folate conjugate wasca. 2× more photocytotoxic towards MCF-7 breast cancer cell line than its parent Pt(iv) complex with a high photoselectivity index (PI > 6.9). The higher photocytotoxicity of the conjugate may be a consequence of its higher cellular accumulation and of the generation of a set of different cytotoxic species, including Pt(ii) photoproducts and several pterin derivatives, which are known to generate ROS.

DEVELOPING A CATALYST FOR HYDROGENATION OF p-NITROBENZOYL-L-GLUTAMIC ACID

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Preparation method of N (4-aminobenzoyl)-L-glutamic acid

The invention provides a preparation method of N (4-aminobenzoyl)-L-glutamic acid. According to the method, p-nitrobenzoic acid is taken as a raw material, BTC/C2H4Cl1 is taken as an acylating chlorination agent, DMF (dimethyl formamide) is added to serve as an initiator, and p-nitrobenzoyl chloride is prepared through reaction at a reflux temperature; p-nitrobenzoyl chloride and sodium glutamate have condensation, and N-(4-nitrobenzoyl)-L-glutamic acid is prepared; N-(4-nitrobenzoyl)-L-glutamic acid is reduced by Pd/C/HCO2NH4, and N (4-aminobenzoyl)-L-glutamic acid is prepared. The preparation method has mild reaction conditions and is simple in process, easy to operate and suitable for industrial production; few three wastes are generated, and a product has high purity and high yield.