RTI-51

RTI-51
Systematic (IUPAC) name
methyl (1R,2S,3S,5S)-3-(4-bromophenyl)-8-methyl-8-azabicyclo[3.2.1]octane-2-carboxylate
Clinical data
Pregnancy cat.  ?
Legal status  ?
Identifiers
CAS number 135367-08-7
ATC code  ?
PubChem CID 22595194
Chemical data
Formula C16H20BrNO2 
Mol. mass 338.240 g/mol
SMILES eMolecules & PubChem
 YesY(what is this?)  (verify)

(–)-2β-Carbomethoxy-3β-(4-bromophenyl)tropane (RTI-51, bromopane) is a semi-synthetic alkaloid in the phenyltropane group of psychostimulant compounds. First publicized in the 1990s, it has not been used enough to have gained a fully established profile. RTI-51 can be expected to have properties lying somewhere in between RTI-31 and RTI-55. Importantly it has a ratio of monoamine reuptake inhibition of D > S > N (1.8:10.6:37.4nM respectively) which is an unusual balance of effects not produced by other commonly used compounds (although RTI-121 is similar, but more DAT selective).[1] It has been used in its 76Br radiolabelled form to map the distribution of dopamine transporters in the brain.[2]

Comparison of halogens
Halogen Atomic № Atomic Weight EN Bond Length
Fluorine 9 19.0 4.0
Chlorine 17 35.5 3.2
Bromine 35 79.9 3.0
Iodine 53 127 2.7

Modern research seems to confirm the above hypothesis.[3] However, earlier work produced more scattered results.[4] Based upon what is obvious from the table, RTI-31, RTI-51, and RTI-55 are all similarly potent TRIs.[5][6]

MAT IC50 (and Ki) for simple phenyltropanes with 1R,2S,3S stereochemistry.[7]
Compound [3H]CFT [3H]DA [3H]Nisoxetine [3H]NE [3H]Paroxetine [3H]5-HT
Cocaine[8] 89.1 275 c.f. 241 3300 (1990) 119 c.f. 161 1050 (45) 177 c.f. 112
WIN 35,065-2 23 49.8 920 (550) 37.2 1960 (178) 173
WIN 35,428 13.9 23.0 835 (503) 38.6 692 (63) 101
RTI-31 1.1 3.68 37 (22) 5.86 44.5 (4.0) 5.00
RTI-113[9] 1.98 5.25 2,926 242 2,340 391
RTI-51 1.7 ? 37.4 (23) ? 10.6 (0.96) ?
RTI-55 1.3 1.96 36 (22) 7.51 4.21 (0.38) 1.74
RTI-32 1.7 7.02 60 (36) 8.42 240 (23) 19.4

Data in Above table from rats brains (1995). More recent work has advocated using cloned human transporter/s.

See also

References

  1. ^ Singh S (March 2000). "Chemistry, design, and structure-activity relationship of cocaine antagonists". Chemical Reviews 100 (3): 925–1024. doi:10.1021/cr9700538. PMID 11749256. 
  2. ^ Loch C, Müller L, Ottaviani M, Halldin C, Farde L, Maziere B. Synthesis of 2β-carbomethoxy-3β-(4-[76Br]bromophenyl)tropane ([76Br]β-CBT), a PET tracer for in vivo imaging of the dopamine uptake sites. Journal of labelled compounds & radiopharmaceuticals. 1995; 36(4):385-392.
  3. ^ Wee, S.; Carroll, F.; Woolverton, W. (2006). "A reduced rate of in vivo dopamine transporter binding is associated with lower relative reinforcing efficacy of stimulants". Neuropsychopharmacology 31 (2): 351–362. doi:10.1038/sj.npp.1300795. PMID 15957006.  edit
  4. ^ Stathis, M; Scheffel; Lever; Boja; Carroll; Kuhar (1995). "Rate of binding of various inhibitors at the dopamine transporter in vivo". Psychopharmacology 119 (4): 376–84. doi:10.1007/BF02245852. PMID 7480516.  edit
  5. ^ Kimmel, HL; Carroll; Kuhar (2001). "Locomotor stimulant effects of novel phenyltropanes in the mouse". Drug and alcohol dependence 65 (1): 25–36. doi:10.1016/S0376-8716(01)00144-2. PMID 11714587.  edit
  6. ^ Kuhar, M. .; Carroll, F. .; Bharat, N. .; Landry, D. . (2001). "Anticocaine catalytic antibodies have no affinity for RTI compounds: implications for treatment". Synapse 41 (2): 176–178. doi:10.1002/syn.1072. PMID 11400184.  edit
  7. ^ Carroll, F. I.; Kotian, P.; Dehghani, A.; Gray, J. L.; Kuzemko, M. A.; Parham, K. A.; Abraham, P.; Lewin, A. H. et al. (1995). "Cocaine and 3 beta-(4'-substituted phenyl)tropane-2 beta-carboxylic acid ester and amide analogues. New high-affinity and selective compounds for the dopamine transporter". Journal of medicinal chemistry 38 (2): 379–388. doi:10.1021/jm00002a020. PMID 7830281.  edit
  8. ^ Kozikowski, A. .; Johnson, K. .; Deschaux, O. .; Bandyopadhyay, B. .; Araldi, G. .; Carmona, G. .; Munzar, P. .; Smith, M. . et al. (2003). "Mixed cocaine agonist/antagonist properties of (+)-methyl 4beta-(4-chlorophenyl)-1-methylpiperidine-3alpha-carboxylate, a piperidine-based analog of cocaine". The Journal of pharmacology and experimental therapeutics 305 (1): 143–150. doi:10.1124/jpet.102.046318. PMID 12649362.  edit
  9. ^ Damaj, MI; Slemmer; Carroll; Martin (1999). "Pharmacological characterization of nicotine's interaction with cocaine and cocaine analogs". The Journal of pharmacology and experimental therapeutics 289 (3): 1229–36. PMID 10336510.  edit