Theophylline-d6 is intended for use as an internal standard for the quantification of theophylline by GC- or LC-MS. Theophylline is an inhibitor of phosphodiesterase. It is also an adenosine A1 and A2 receptor antagonist. Theophylline induces relaxation of isolated cat bronchial smooth muscle segments precontracted with acetylcholine. It inhibits ovalbumin-induced increases in bronchoalveolar lavage fluid (BALF) eosinophil infiltration in an ovalbumin-sensitized mouse model of allergic asthma. Formulations containing theophylline have been used in the treatment of asthma and chronic obstructive pulmonary disease (COPD).
NCT-501 hydrochloride is a highly potent and selective inhibitor of aldehyde dehydrogenase 1A1 (ALDH1A1), which is based on theophylline. It effectively inhibits hALDH1A1 with an IC50 value of 40 nM, exhibiting superior selectivity towards hALDH1A1 compared to other ALDH isozymes and dehydrogenases such as hALDH1B1, hALDH3A1, and hALDH2 (with IC50 values exceeding 57 μM).