All Photos(1)




LDH-A Inhibitor III, NHI-1

Sign Into View Organizational & Contract Pricing

LDH-A Inhibitor III, NHI-1, 1-Hydroxy-6-phenyl-4-trifluoromethyl-1H-indole-2-carboxylic acid, Lactate Dehydrogenase A Inhibitor III, LDH-M Inhibitor III
Empirical Formula (Hill Notation):
CAS Number:
Molecular Weight:


≥98% (HPLC)

Quality Level





storage condition

OK to freeze
protect from light




DMSO: 100 mg/mL

storage temp.


General description

A cell-permeable, both NADH and pyruvate-competitive isoform A-selective LDH inhibitor. Exhibits enhanced anticancer activity under hypoxic conditions.
A cell-permeable, non-cytotoxic N-hydroxyindole (NHI) carboxylate that acts as a potent, reversible, and isoform selective inhibitor of lactic dehydrogenase (LDH) A/LDH-1. Inhibition appears to be competitive with respect to both pyruvate (Ki = 4.7 µM) and NADH (cofactor; Ki = 8.9 µM). Acts by occupying the whole substrate pocket and part of the cofactor pocket of LDH-A. Blocks the growth of various cancer cell lines by causing an arrest at G1 phase and inducing apoptosis (IC50 = 10.8, 10.6, 11.4, and 31.5 µM for A2780/cOHP, MSTO-211H, NIH-H28, and H630 cells, respectively). Exhibits enhanced anticancer activity under hypoxic conditions (GI50 = 0.90 µM/hypoxia vs. 16.3 µM/normoxia in LPC006 cultures) and strongly synergizes with gemcitabine (Cat. No. 504594).

Please note that the molecular weight for this compound is batch-specific due to variable water content. Please refer to the vial label or the certificate of analysis for the batch-specific molecular weight. The molecular weight provided represents the baseline molecular weight without water.
A cell-permeable, noncytotoxic NHI (N-hydroxyindole) carboxylate that acts as an isoform A-selective LDH inhibitor (87% inhibition of hLDH-A4 vs 11% inhibition of hLDH-B4 at 125 µM; [NADH] = 25 µM & [pyruvate] = 2 mM) in a competitive manner with respect to both NADH (Ki = 8.9 µM; [pyruvate] = 2 mM) and pyruvate (Ki = 4.7 µM; [NADH] = 200 µM). Shown to effectively inhibit de novo D-[1,6-13C2] glucose-derived lactate production in HeLa cultures (80% and <5% of control Lac/Glu ratio in 12 h, respectively, with 400 and 500 µM inhibitor) and exhibit enhanced anticancer activity under hypoxic conditions (GI50 by SRB assays = 0.90 µM/hypoxia vs. 16.3 µM/normoxia in LPC006 cultures), while diplaying little antiproliferation activity toward non-tumorigenic hTERT-HPNE (ductal pancreatic) and Hs27 (skin fibroblast) even at concentrations as high as 100 µM;.

Biochem/physiol Actions

Cell permeable: yes
Primary Target
Target IC50: 10.8, 10.6, 11.4, and 31.5 &micro


Toxicity: Standard Handling (A)


Following reconstitution, aliquot and freeze (-20°C). Stock solutions are stable for up to 3 months at -20°C.

Other Notes

Maftouh, M., et al. 2014. Br. J. Cancer.110, 172.
Granchi, C., et al. 2011. J. Med. Chem.54, 1599.

Legal Information

CALBIOCHEM is a registered trademark of Merck KGaA, Darmstadt, Germany

Storage Class

11 - Combustible Solids




Not applicable


Not applicable

Certificates of Analysis (COA)

Search for Certificates of Analysis (COA) by entering the products Lot/Batch Number. Lot and Batch Numbers can be found on a product’s label following the words ‘Lot’ or ‘Batch’.

Already Own This Product?

Documents related to the products that you have purchased in the past have been gathered in the Document Library for your convenience.

Visit the Document Library

Difficulty Finding Your Product Or Lot/Batch Number?

Product numbers are combined with Pack Sizes/Quantity when displayed on the website (example: T1503-25G). Please make sure you enter ONLY the product number in the Product Number field (example: T1503).


Product Number
Pack Size/Quantity

Additional examples:





enter as 1.000309185)

Having trouble? Feel free to contact Technical Service for assistance.

Lot and Batch Numbers can be found on a product's label following the words 'Lot' or 'Batch'.

Aldrich Products

  • For a lot number such as TO09019TO, enter it as 09019TO (without the first two letters 'TO').

  • For a lot number with a filling-code such as 05427ES-021, enter it as 05427ES (without the filling-code '-021').

  • For a lot number with a filling-code such as STBB0728K9, enter it as STBB0728 without the filling-code 'K9'.

Not Finding What You Are Looking For?

In some cases, a COA may not be available online. If your search was unable to find the COA you can request one.

Request COA

Our team of scientists has experience in all areas of research including Life Science, Material Science, Chemical Synthesis, Chromatography, Analytical and many others.

Contact Technical Service