WARNING: This product is for research use only, not for human or veterinary use.

MedKoo CAT#: 530569

CAS#: 22503-72-6

Description: IDRA-21 is a positive AMPA receptor modulator. IDRA-21 inhibits synaptic and extrasynaptic NMDA receptor mediated events in cultured cerebellar granule cells. IDRA 21 enhances ischemic hippocampal neuron injury.

Price and Availability

Size Price Shipping out time Quantity
100mg USD 250 2 Weeks
200mg USD 450 2 Weeks
500mg USD 950 2 Weeks
1g USD 1750 2 Weeks
2g USD 2950 2 Weeks
5g USD 4950 2 Weeks
10g USD 5950 2 Weeks
20g USD 8950 2 Weeks
50g USD 16550 2 Weeks
Inquire bulk and customized quantity

Pricing updated 2021-01-19. Prices are subject to change without notice.

IDRA-21, purity > 98%, is in stock. Current shipping out time is about 2 weeks after order is received. CoA, QC data and MSDS documents are available in one week after order is received.

Chemical Structure


Theoretical Analysis

MedKoo Cat#: 530569
Name: IDRA-21
CAS#: 22503-72-6
Chemical Formula: C8H9ClN2O2S
Exact Mass: 232.0073
Molecular Weight: 232.682
Elemental Analysis: C, 41.30; H, 3.90; Cl, 15.24; N, 12.04; O, 13.75; S, 13.78

Synonym: IDRA-21; IDRA 21; IDRA21.

IUPAC/Chemical Name: 7-Chloro-3-methyl-3-4-dihydro-2H-1,2,4 benzothiadiazine S,S-dioxide


InChi Code: InChI=1S/C8H9ClN2O2S/c1-5-10-7-3-2-6(9)4-8(7)14(12,13)11-5/h2-5,10-11H,1H3

SMILES Code: CC(NC1=CC=C(Cl)C=C12)NS2(=O)=O

Technical Data

White to off-white solid powder

>98% (or refer to the Certificate of Analysis)

Shipping Condition:
Shipped under ambient temperature as non-hazardous chemical. This product is stable enough for a few weeks during ordinary shipping and time spent in Customs.

Storage Condition:
Dry, dark and at 0 - 4 C for short term (days to weeks) or -20 C for long term (months to years).

Soluble in DMSO

Shelf Life:
>2 years if stored properly

Drug Formulation:
This drug may be formulated in DMSO

Stock Solution Storage:
0 - 4 C for short term (days to weeks), or -20 C for long term (months).

HS Tariff Code:


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2: Buccafusco JJ, Weiser T, Winter K, Klinder K, Terry AV. The effects of IDRA 21, a positive modulator of the AMPA receptor, on delayed matching performance by young and aged rhesus monkeys. Neuropharmacology. 2004 Jan;46(1):10-22. PubMed PMID: 14654093.

3: Losi G, Puia G, Braghiroli D, Baraldi M. IDRA-21, a positive AMPA receptor modulator, inhibits synaptic and extrasynaptic NMDA receptor mediated events in cultured cerebellar granule cells. Neuropharmacology. 2004 Jun;46(8):1105-13. PubMed PMID: 15111017.

4: Yamada KA, Covey DF, Hsu CY, Hu R, Hu Y, He YY. The diazoxide derivative IDRA 21 enhances ischemic hippocampal neuron injury. Ann Neurol. 1998 May;43(5):664-9. PubMed PMID: 9585363.

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7: Zivkovic I, Thompson DM, Bertolino M, Uzunov D, DiBella M, Costa E, Guidotti A. 7-Chloro-3-methyl-3-4-dihydro-2H-1,2,4 benzothiadiazine S,S-dioxide (IDRA 21): a benzothiadiazine derivative that enhances cognition by attenuating DL-alpha-amino-2,3-dihydro-5-methyl-3-oxo-4-isoxazolepropanoic acid (AMPA) receptor desensitization. J Pharmacol Exp Ther. 1995 Jan;272(1):300-9. PubMed PMID: 7815345.

8: Thompson DM, Guidotti A, DiBella M, Costa E. 7-Chloro-3-methyl-3,4-dihydro-2H-1,2,4-benzothiadiazine S,S-dioxide (IDRA 21), a congener of aniracetam, potently abates pharmacologically induced cognitive impairments in patas monkeys. Proc Natl Acad Sci U S A. 1995 Aug 15;92(17):7667-71. PubMed PMID: 7644474; PubMed Central PMCID: PMC41206.

9: Arai A, Guidotti A, Costa E, Lynch G. Effect of the AMPA receptor modulator IDRA 21 on LTP in hippocampal slices. Neuroreport. 1996 Sep 2;7(13):2211-5. PubMed PMID: 8930991.

10: Phillips D, Sonnenberg J, Arai AC, Vaswani R, Krutzik PO, Kleisli T, Kessler M, Granger R, Lynch G, Richard Chamberlin A. 5'-alkyl-benzothiadiazides: a new subgroup of AMPA receptor modulators with improved affinity. Bioorg Med Chem. 2002 May;10(5):1229-48. PubMed PMID: 11886787.

11: Puia G, Losi G, Razzini G, Braghiroli D, Di Bella M, Baraldi M. Modulation of kainate--activated currents by diazoxide and cyclothiazide analogues (IDRA) in cerebellar granule neurons. Prog Neuropsychopharmacol Biol Psychiatry. 2000 Aug;24(6):1007-15. PubMed PMID: 11041540.

12: Impagnatiello F, Oberto A, Longone P, Costa E, Guidotti A. 7-Chloro-3-methyl-3,4-dihydro-2H-1,2,4-benzothiadiazine S,S-dioxide: a partial modulator of AMPA receptor desensitization devoid of neurotoxicity. Proc Natl Acad Sci U S A. 1997 Jun 24;94(13):7053-8. PubMed PMID: 9192690; PubMed Central PMCID: PMC21283.

13: Padmanabhan B. Identification of novel modulators for ionotropic glutamate receptor, iGluA2 by in-silico screening. Theor Biol Med Model. 2013 Jul 15;10:46. doi: 10.1186/1742-4682-10-46. PubMed PMID: 23855825; PubMed Central PMCID: PMC3718743.

14: Vandesquille M, Carrié I, Louis C, Beracochea D, Lestage P. Effects of positive modulators of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)-type glutamate receptors in a benzodiazepine-induced deficit of spatial discrimination in mice. J Psychopharmacol. 2012 Jun;26(6):845-56. doi: 10.1177/0269881111416692. Epub 2011 Sep 2. PubMed PMID: 21890586.

15: Arai AC, Xia YF, Kessler M, Phillips D, Chamberlin R, Granger R, Lynch G. Effects of 5'-alkyl-benzothiadiazides on (R,S)-alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor biophysics and synaptic responses. Mol Pharmacol. 2002 Sep;62(3):566-77. PubMed PMID: 12181433.

16: Nagarajan N, Quast C, Boxall AR, Shahid M, Rosenmund C. Mechanism and impact of allosteric AMPA receptor modulation by the ampakine CX546. Neuropharmacology. 2001 Nov;41(6):650-63. PubMed PMID: 11640919.

17: Lockhart BP, Rodriguez M, Mourlevat S, Peron P, Catesson S, Villain N, Galizzi JP, Boutin JA, Lestage P. S18986: a positive modulator of AMPA-receptors enhances (S)-AMPA-mediated BDNF mRNA and protein expression in rat primary cortical neuronal cultures. Eur J Pharmacol. 2007 Apr 30;561(1-3):23-31. Epub 2007 Feb 1. PubMed PMID: 17331496.

18: Uzunov DP, Zivkovich I, Pirkle WH, Costa E, Guidotti A. Enantiomeric resolution with a new chiral stationary phase of 7-chloro-3-methyl-3,4-dihydro-2H-1,2,4-benzothiadiazine S,S-dioxide, a cognition-enhancing benzothiadiazine derivative. J Pharm Sci. 1995 Aug;84(8):937-42. PubMed PMID: 7500277.

19: Kertész S, Kapus G, Lévay G. Interactions of allosteric modulators of AMPA/kainate receptors on spreading depression in the chicken retina. Brain Res. 2004 Oct 29;1025(1-2):123-9. PubMed PMID: 15464752.

20: Cannazza G, Jozwiak K, Parenti C, Braghiroli D, Carrozzo MM, Puia G, Losi G, Baraldi M, Lindner W, Wainer IW. A novel class of allosteric modulators of AMPA/Kainate receptors. Bioorg Med Chem Lett. 2009 Feb 15;19(4):1254-7. doi: 10.1016/j.bmcl.2008.12.094. Epub 2008 Dec 30. PubMed PMID: 19162477; PubMed Central PMCID: PMC2656388.