rod-188 rod-188 rod-188 is a sedative drug that was structurally derived from the gabaa antagonist bicuculline by a team at roche. unlike bicuculline, rod-188 acts as an agonist at gabaa receptors, being a positive allosteric modulator acting at a novel binding site distinct from those of benzodiazepines, barbiturates or muscimol, with its strongest effect produced at the α6β2γ2 subtype of the gabaa receptor. rod-188 is one of a number of related compounds acting at this novel modulatory site, some of which also act at benzodiazepine receptors. rod-188clinical dataatc codenonelegal statuslegal status in general: uncontrolled identifiers iupac name (5r)-5-dihydrofuran-2(3h)-one pubchem cid9842377chemspider8018092chemical and physical dataformulac20h21no4smolar mass371.45 g·mol−13d model (jsmol)interactive image smiles cc1ccc(cc1)s(=o)(=o)n2ccc4ccccc423ccc(=o)o3 (verify)