cyclothiazide cyclothiazide cyclothiazide (anhydron, acquirel, doburil, fluidil, renazide, tensodiural, valmiran), sometimes abbreviated ctz, is a benzothiadiazide (thiazide) diuretic and antihypertensive that was originally introduced in the united states in 1963 by eli lilly and was subsequently also marketed in europe and japan. related drugs include diazoxide, hydrochlorothiazide, and chlorothiazide. cyclothiazideclinical dataatc codec03aa09 (who) legal statuslegal status in general: ℞ (prescription only) identifiers iupac name 3-(bicyclohept-5-en-2-yl)-6-chloro-3,4-dihydro-2h-1,2,4-benzothiadiazine-7-sulfonamide 1,1-dioxide cas number2259-96-3 ypubchem cid2910iuphar/bps4167drugbankdb00606 nchemspider4535011 nuniip71u09g5bwkeggd01256 ychemblchembl61593 ncomptox dashboard (epa)dtxsid3022871 echa infocard100.017.146 chemical and physical dataformulac14h16cln3o4s2molar mass389.87 g·mol−13d model (jsmol)interactive image smiles o=s(=o)(c1c(cl)cc2c(c1)s(=o)(=o)nc(n2)c43\c=c/(c3)c4)n inchi inchi=1s/c14h16cln3o4s2/c15-10-5-11-13(6-12(10)23(16,19)20)24(21,22)18-14(17-11)9-4-7-1-2-8(9)3-7/h1-2,5-9,14,17-18h,3-4h2,(h2,16,19,20)/t7-,8+,9?,14?/m0/s1 nkey:bocukuhclicsiy-qjwljzlasa-n n ny (what is this?) (verify) in 1993, it was discovered that cyclothiazide is a positive allosteric modulator of the ampa and kainate receptors, capable of reducing or essentially eliminating rapid desensitization of the former receptor, and potentiating ampa-mediated glutamate currents by as much as 18-fold at the highest concentration tested (100 μm). additionally, in 2003, cyclothiazide was also found to act as a gabaa receptor negative allosteric modulator, potently inhibiting gabaa-mediated currents. in animals it is a powerful convulsant, robustly enhancing epileptiform activity and inducing seizures, but without producing any apparent neuronal death. cyclothiazide has been found to act as a non-competitive antagonist of the mglur1. it is selective for mglur1 over other metabotropic glutamate receptors. synthesis cyclothiazide synthesis: e. müller, k. hasspacher, u.s. patent 3,275,625 (1966 to boehringer ingelheim).