Back
HuagongsheHuagongshe Chemistry Print Report · For research reference only
HCID 405802Generated: October 29, 2026

5-methyl-4-oxo-3H,4H-thieno[2,3-d]pyrimidine-6-carboxylic acid

5-methyl-4-oxo-3H-thieno[2,3-d]pyrimidine-6-carboxylic acid · 5-Methyl-4-oxo-3H,4H-thieno[2,3-d]pyrimidine-6-carboxylic acid · 5-Methyl-4-oxo-3,4-dihydro-thieno[2,3-d]pyriMidine-6-carboxylic · 5-methyl-4-oxo-1,4-dihydrothieno[2,3-d]pyrimidine-6-carboxylic acid · Thieno[2,3-d]pyrimidine-6-carboxylic acid, 1,4-dihydro-5-methyl-4-oxo- · 5-methyl-4-oxo-3,4-dihydrothieno[2,3-d]pyrimidine-6-carboxylic acid(SALTDATA: FREE)

https://huagongshe.com/en/chemical/405802

5-methyl-4-oxo-3H,4H-thieno[2,3-d]pyrimidine-6-carboxylic acid molecular structure

Identifiers & Physical Properties

CAS No.101667-97-4
Molecular formulaC8H6N2O3S
Average molar mass210.21 g/mol
Monoisotopic mass210.00991305 g/mol
SMILESCc1c(C(=O)O)sc2nc[nH]c(=O)c12
InChIKeyCYNGLBSDKJIAOD-UHFFFAOYSA-N
PubChem CID405802
ChEMBLCHEMBL1965658
EC No.675-249-7
DTXSIDDTXSID50328084

Chemical & Physical Properties

XLogP0.9
Topological polar surface area107
Hydrogen bond donors2
Hydrogen bond acceptors5
Rotatable bonds1
Heavy atoms14
Formal charge0
Complexity318
Melting point300 °C(Solv: 1,4-dioxane (123-91-1))
Boiling point571.8±50.0 °C(Predicted)
Density1.76±0.1 g/cm3(Predicted)
pKa (acidity coefficient)3.72±0.20(Predicted)
GHS pictogramGHS07
Signal wordWarning
GHS hazard statementsH302
GHS precautionary statementsP501-P270-P264-P301+P312+P330
Risk statements (R)36/37/38
Safety statements (S)26-36
Hazard classIRRITANT
Customs code29335990

Safety & Regulations

GHS classificationWarningH302 (50%): Harmful if swallowed [Warning Acute toxicity, oral]P261, P264, P264+P265, P270, P271, P280, P301+P317, P302+P352, P304+P340, P305+P351+P338, P319, P321, P330, P332+P317, P337+P317, P362+P364, P403+P233, P405, and P501 (click each P-code to see the statement)Aggregated GHS information provided per 2 reports by companies from 2 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.
Hazard Classes and CategoriesAcute Tox. 4 (50%)
Customs code29335990
Risk statements (R)36/37/38
Signal wordWarning
GHS pictogramGHS07
Safety statements (S)26-36
Hazard classIRRITANT
GHS hazard statementsH302
GHS precautionary statementsP501-P270-P264-P301+P312+P330