MolGraph
CompoundsDocumentationComplianceAbout
MolGraph

Research chemical sourcing and molecular building block RFQ workflows.

MolGraph is operated by Tessorix Inc.

support@molgraph.com

Products are intended for laboratory research use only and are not for human or veterinary use.

Compounds

  • Compound catalog
  • CAS Search

Company

  • About
  • Contact

Documentation

  • Quality Documentation
  • SDS Disclaimer

Compliance

  • Compliance

Legal

  • Terms
  • Privacy

Copyright © 2026 MolGraph. All Rights Reserved.

Home/Compounds/CAS 99-50-3
Formula C7H6O4MW 154.12Research-use catalog entryCOA/SDS by request

Protocatechuic Acid

CAS Number: 99-50-3

Sourcing & RFQ

Submit an RFQ to review pricing, availability, lead time, pack size, purity, COA, and supplier SDS for this catalog entry.

Available options

Available Options

Package
1 g
Purity
98%
Price
Request review
Availability
Shipping review required
Delivery
Shipping review required
Package
1 kg
Purity
98%
Price
Request review
Availability
Shipping review required
Delivery
Shipping review required
Package
1 mg
Purity
98%
Price
Request review
Availability
Shipping review required
Delivery
Shipping review required
Package
100 g
Purity
98%
Price
Request review
Availability
Shipping review required
Delivery
Shipping review required
Package
25 g
Purity
98%
Price
Request review
Availability
Shipping review required
Delivery
Shipping review required
Package
5 g
Purity
98%
Price
Request review
Availability
Shipping review required
Delivery
Shipping review required
Package
500 g
Purity
98%
Price
Request review
Availability
Shipping review required
Delivery
Shipping review required

Shipping review is required before pricing or stock can be confirmed publicly. Shipping, duties, and documentation fees are confirmed before order acceptance.

Loading RDKit molecule structure...
InChIKey: YQUVCSBJEUQKSH-UHFFFAOYSA-NC7H6O4 | MW 154.12

Chemical Absolute Identifiers

CAS Number

99-50-3

PubChem CID

72

Molecular Formula

C7H6O4

Molecular Weight

154.12 g/mol

Exact Mass

154.026609

InChIKey

YQUVCSBJEUQKSH-UHFFFAOYSA-N

IUPAC Name

3,4-dihydroxybenzoic acid

SMILES String

O=C(O)c1ccc(O)c(O)c1

Physical Properties

Melting Point

221.0 °C

pKa

4.26

Show more physical data

Vapor Pressure

Estimated very low; unit not specified

Properties are provided as catalog reference data and may be confirmed through supplier documentation when required.

Catalog Facts

Structural features

Protocatechuic Acid (CAS 99-50-3) is listed in the Pharmaceutical Intermediates portfolio, with molecular formula C7H6O4 and molecular weight 154. 12 g/mol.

Sourcing context

Catalog reference for RFQ preparation, supplier confirmation, and research chemical sourcing review.

Research use context

Intended for research-stage medicinal chemistry and intermediate synthesis workflows.

Documentation needs

COA/SDS status, availability, lead time, pack size, and shipment documentation can be confirmed during quotation.

Applications & Classification

Pharmaceutical Intermediate ResearchResearch intermediateCustom synthesis building blockPharmaceutical intermediate researchResearch chemical sourcingCustom synthesis and catalog availability reviewCOA, SDS, pricing, and fulfillment workflow
Biological target reference

ChEMBL reports experimental activity evidence for: Carbonic anhydrase 6 (Homo sapiens) — 2 assays; 3-dehydroquinate synthase (Escherichia coli K-12) — 2 assays; DNA polymerase beta (Rattus norvegicus) — 3 assays; Tyrosinase (Agaricus bisporus) — 3 assays; Estrogen receptor (Homo sapiens) — 2 assays. These records describe research assays and do not establish therapeutic efficacy or clinical use.

Carbonic anhydrase 6

Homo sapiens · SINGLE PROTEIN · 2 qualifying assays · 2 documents · best pChEMBL 5.33

Experimental evidence source: ChEMBL

3-dehydroquinate synthase

Escherichia coli K-12 · SINGLE PROTEIN · 2 qualifying assays · 1 documents · best pChEMBL 4.36

Experimental evidence source: ChEMBL

DNA polymerase beta

Rattus norvegicus · SINGLE PROTEIN · 3 qualifying assays · 1 documents

Experimental evidence source: ChEMBL

Tyrosinase

Agaricus bisporus · SINGLE PROTEIN · 3 qualifying assays · 2 documents

Experimental evidence source: ChEMBL

Estrogen receptor

Homo sapiens · SINGLE PROTEIN · 2 qualifying assays · 1 documents

Experimental evidence source: ChEMBL

Safety & Handling

Safety and handling reference content is available through documentation requests.

For supplier-issued SDS, request documentation before handling, storage, shipment, or procurement decisions.

Preliminary Safety Reference

For supplier-issued SDS or COA, submit a documentation request.

Safety Reference / SDS Request

Names & Synonyms / External Identifiers

Chemical Name

Protocatechuic Acid

Names & Synonyms

4-Carboxy-1,2-dihydroxybenzeneProtocatehuic acid4,5-Dihydroxybenzoic acidFEMA NO. 4430protocatechuate
Show all synonyms
Benzoic acid, 3,4-dihydroxy-3,4-Dihydroxy Benzoic AcidprotocatechuicacidCarbohydroquinonic acidCCRIS 62913,4-dihydroxy-benzoic acidCatechol-4-carboxylic Acid3,4-Dihydroxybenzoicacid1ykp3, 4-Dihydroxybenzoic acidb-Resorcylatebeta-Resorcylateprocatechuic acidProtocatechicAcid
External Identifiers
EC NUMBER: 202-760-0DSSTOX SUBSTANCE ID: DTXSID4021212CHEMBL ID: CHEMBL37537CHEBI ID: CHEBI:36062UNII: 36R5QJ8L4BDRUGBANK ID: DB03946HMDB ID: HMDB0001856KEGG ID: C00230METABOLOMICS WORKBENCH ID: 37892WIKIDATA ID: Q418599
Experimental Spectrum References
13C NMR Spectra1D NMR Spectra1H NMR SpectraATR-IR SpectraFTIR SpectraRaman Spectra
Literature & Patent References
DOI 10.1021/acs.jmedchem.5c004183,5-Dihydroxybenzoic Acid as a Potent Inhibitor of Tyrosine Phenol-Lyase Decreases Fecal Phenol Levels in Mice.PMID 401731063,5-Dihydroxybenzoic Acid as a Potent Inhibitor of Tyrosine Phenol-Lyase Decreases Fecal Phenol Levels in Mice.DOI 10.1016/j.bmcl.2022.128722Polyphenolic compounds: Synthesis, assessment of antimicrobial effect and enzymes inhibition against important medicinal enzymes with computational details.PMID 35395370Polyphenolic compounds: Synthesis, assessment of antimicrobial effect and enzymes inhibition against important medicinal enzymes with computational details.DOI 10.1016/j.ejmech.2021.113804Synthetically-tailored and nature-derived dual COX-2/5-LOX inhibitors: Structural aspects and SAR.PMID 34479036Synthetically-tailored and nature-derived dual COX-2/5-LOX inhibitors: Structural aspects and SAR.DOI 10.1016/j.bmc.2020.115642An assay for DNA polymerase β lyase inhibitors that engage the catalytic nucleophile for binding.DOI 10.1016/j.ejmech.2020.112268Dihydrofolate reductase inhibitors for use as antimicrobial agents.

Documentation & Compliance Facts

Compliance Facts

Shipment review: Required

Documentation available by request

Certificate of Analysis (COA): By request

Supplier Safety Data Sheet (SDS): By request

Purity and pack size confirmation: By request

Availability and lead time review: Confirmed by RFQ

Shipment documentation review: By request

For supplier-issued documentation by request, use the RFQ actions on this page.Review preliminary safety reference

What happens after RFQ

  1. 1We review the CAS identity, quantity, and documentation request.
  2. 2We check sourcing options, supplier availability, COA/SDS, purity, pack size, and lead time.
  3. 3We review destination and shipment documentation needs when applicable.
  4. 4We follow up with a quotation or clarification request.

Text Reference Cues

Show non-linked catalog cues

Non-public related references

3-(Cyclopropylmethoxy)-4-hydroxybenzoic acidCAS 1243391-44-7
3,4-Bis(acetyloxy)benzoic acidCAS 58534-64-8
N-(3,5-dichloropyridin-4-yl)-3,4-dihydroxybenzamideCAS 1412448-29-3
Methyl 3-acetyl-4-hydroxybenzoateCAS 57009-12-8
3-(Cyclopropylmethoxy)-4-(difluoromethoxy)benzoic AcidCAS 162401-62-9

Non-public references are shown as text only and do not imply equivalence, availability, or shared use.

Catalog navigation

Related Catalog Entries

Other public CAS pages in this catalog. These links support navigation across additional intermediates and do not imply equivalence, availability, or shared use.

CAS 1243391-44-73-(Cyclopropylmethoxy)-4-hydroxybenzoic acidCAS 58534-64-83,4-Bis(acetyloxy)benzoic acidCAS 1412448-29-3N-(3,5-dichloropyridin-4-yl)-3,4-dihydroxybenzamideCAS 103-85-5PhenylthioureaCAS 121-34-6Vanillic AcidCAS 14222-60-7ProthionamideCAS 99-96-74-Hydroxybenzoic AcidCAS 10083-24-6PiceatannolCAS 1002310-00-0Tert-butyl 1-(2-chloro-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)ethylcarbamateCAS 1005174-17-3(E)-3-(2-Propyl-6-(trifluoromethyl)pyridin-3-yl)acrylic acid

RFQ questions for CAS 99-50-3

What are the key identifiers for Protocatechuic Acid (CAS 99-50-3)?

Protocatechuic Acid is identified by CAS 99-50-3, with molecular formula C7H6O4, molecular weight 154.12, InChIKey YQUVCSBJEUQKSH-UHFFFAOYSA-N.

Does CAS 99-50-3 have reported biological target evidence?

ChEMBL contains qualifying experimental assay evidence associated with Carbonic anhydrase 6, 3-dehydroquinate synthase, DNA polymerase beta, Tyrosinase, Estrogen receptor. These records do not establish therapeutic efficacy or clinical use.

Can I request a COA for CAS 99-50-3?

Yes. Submit an RFQ and specify COA requirements. Lot-specific COA depends on supplier confirmation.

Can I request supplier SDS for Protocatechuic Acid?

Yes. Supplier SDS can be requested through the RFQ workflow before handling, storage, shipment, or procurement decisions.

Is CAS 99-50-3 available for quotation?

Availability, pack size, lead time, and pricing are confirmed through RFQ.

Can MolGraph support bulk sourcing or custom synthesis review?

Submit the CAS number, quantity, purity requirement, and destination country for sourcing review.