5-AMINO-PYRAZINE-2-CARBOXYLIC ACID

5-Aminopyrazine-2-carboxylic acid (CAS 40155-43-9) is a strategically bifunctional pyrazine scaffold engineered for heterocyclic diversification, pharmaceutical intermediate synthesis, and antifolate drug development. This molecule integrates an electron-deficient pyrazine core—a six-membered aromatic diazine ring with nitrogen atoms at para positions (1,4)—with an amino substituent at the C5 position and a carboxylic acid group at the C2 position. The C2-carboxylic acid moiety serves as a versatile handle for amide coupling, esterification, or salt formation, while the C5-amino group provides orthogonal reactivity for acylation, alkylation, diazotization, or heterocyclic fusion. This dual-functionality architecture is particularly valuable for constructing fused heterocycles (pyrazino-fused systems), kinase inhibitor cores, and antimetabolite analogs (e.g., methotrexate derivatives) where the aminoacid-pyrazine motif optimizes target engagement through specific hydrogen-bonding patterns and ionic interactions. Compared to halogenated pyrazines, this compound offers direct access to amide/peptide-like structures without requiring cross-coupling steps. Manufactured with purity ≥98% under controlled conditions, it supports drug discovery programs requiring modular access to functionalized diazine architectures with tunable solubility and reactivity.

Property

Product Name	5-Aminopyrazine-2-carboxylic acid
CAS Number	40155-43-9
Chinese Name	5-氨基吡嗪 -2-羧酸
Synonyms	5-Amino-2-pyrazinecarboxylic acid; Pyrazine-2-carboxylic acid, 5-amino-; C₅H₅N₃O₂ heterocycle; 5-APCA
Chinese Synonyms	5-氨基 -2-吡嗪羧酸; 5-氨基吡嗪 -2-甲酸; 氨基吡嗪羧酸; 5-位氨基 -2-位羧酸吡嗪
Molecular Formula	C₅H₅N₃O₂
Molecular Weight	139.11 g/mol
Purity	≥ 98% (HPLC area normalization)
Product Category	Pharmaceutical Intermediates / Pyrazine Derivatives / Amino Acid Heterocycles
Appearance	Light brown to off-white solid
Melting Point	>250°C (decomposition, literature reference recommended)
pKa	~2.5 (COOH), ~5.5 (NH₃⁺, estimated; zwitterionic potential)
Storage Conditions	Store in a cool, dry, well-ventilated area away from light and moisture. Keep container tightly closed under inert atmosphere (nitrogen). Protect from strong oxidizing agents to avoid amino group oxidation.
Shelf Life	24 months under recommended storage conditions
Packaging	100mg/vial, 500mg/vial, 1g/bottle, 5g/bottle, or customized according to customer requirements
Applications	Kinase inhibitor synthesis, antifolate drug development (methotrexate analogs), heterocyclic library construction (pyrazino-fused systems), amide coupling for drug conjugates, ligand synthesis for coordination chemistry, diazotization reactions
Reactivity	Suitable for amino group acylation/alkylation, carboxylic acid activation (EDC/HATU), esterification, heterocyclic fusion, electrophilic aromatic substitution at C3/C6, and salt formation
Special Note	✅ Bifunctional Amino Acid Scaffold—C2-COOH for coupling, C5-NH₂ for derivatization. Electron-deficient pyrazine core provides unique binding geometry vs. phenylalanine analogs. Part of our pyrazine building block series.