Benztropine-13C-d3 (mesylate)

Benztropine-13C-d3 is intended for use as an internal standard for the quantification of benztropine by GC- or LC-MS. Benztropine is an antagonist of M1 muscarinic acetylcholine receptors (Ki = 0.59 nM in rat brain membranes).1 It is selective for M1 receptors over the serotonin transporter (Ki = 5,150 nM), however, it also binds to the dopamine transporter and inhibits dopamine reuptake (Kis = 237 and 130 nM, respectively).1,2,3 Benztropine also inhibits acid sphingomyelinase by 87% when used at a concentration of 10 mM.4 Formulations containing benztropine have been used in the management of Parkinson's disease symptoms such as involuntary tremor and dystonia.

|1. Zhang, Y., Joseph, D.B., Bowen, W.D., et al. Synthesis and biological evaluation of tropane-like 1-[2-[bis(4-fluorophenyl)methoxy]ethyl]-4-(3-phenylpropyl)piperazine (GBR 12909) analogues. J. Med. Chem. 44(23), 3937-3945 (2001).|2. Schmitt, K.C., Zhen, J., Kharkar, P., et al. Interaction of cocaine-, benztropine-, and GBR12909- like compounds with wildtype and mutant human dopamine transporters: Molecular features that differentially determine antagonist binding properties. J. Neurochem. 107(4), 928-940 (2008).|3. Ukairo, O.T., Bondi, C.D., Newman, A.H., et al. Recognition of benztropine by the dopamine transporter (DAT) differs from that of the classical dopamine uptake inhibitors cocaine, methylphenidate, and mazindol as a function of a DAT transmembrane 1 aspartic acid residue. J. Pharmacol. Exp. Ther. 314(2), 575-583 (2005).|4. Kornhuber, J., Muehlbacher, M., Trapp, S., et al. Identification of novel functional inhibitors of acid sphingomyelinase. PLoS One 6(8), 1-13 (2011).