Article · Wikipedia archive · Last revised Jun 24, 2026

HDMP-28

HDMP-28 or methylnaphthidate is a stimulant drug of the piperidine and naphthylaminopropane groups, closely related to methylphenidate (Ritalin), but with the benzene ring replaced by naphthalene. It is a potent dopamine reuptake inhibitor, with several times the potency of methylphenidate and a short duration of action, and is a structural isomer of another potent dopamine reuptake inhibitor, N,O-Dimethyl-4-(2-naphthyl)piperidine-3-carboxylate. It has been sold as a designer drug since around 2015.

Last revised
Jun 24, 2026
Read time
≈ 3 min
Length
646 w
Citations
7
Source
HDMP-28
Legal status
Legal status
Identifiers
  • Methyl (naphthalen-2-yl)(piperidin-2-yl)acetate
CAS Number
PubChem CID
ChemSpider
UNII
Chemical and physical data
FormulaC18H21NO2
Molar mass283.371 g·mol−1
3D model (JSmol)
  • O=C(OC)[C@H](C1=CC2=C(C=C1)C=CC=C2)[C@]3([H])CCCCN3

  • O=C(OC)[C@H](c2cc1ccccc1cc2)[C@@H]3NCCCC3
  • InChI=1S/C18H21NO2/c1-21-18(20)17(16-8-4-5-11-19-16)15-10-9-13-6-2-3-7-14(13)12-15/h2-3,6-7,9-10,12,16-17,19H,4-5,8,11H2,1H3/t16-,17-/m1/s1 ☒N
  • Key:DNRNSIJBSCBESJ-IAGOWNOFSA-N ☒N
 ☒NcheckY (what is this?)  (verify)

HDMP-28 or methylnaphthidate is a stimulant drug of the piperidine and naphthylaminopropane groups, closely related to methylphenidate (Ritalin), but with the benzene ring replaced by naphthalene. It is a potent dopamine reuptake inhibitor, with several times the potency of methylphenidate and a short duration of action,1 and is a structural isomer of another potent dopamine reuptake inhibitor, N,O-Dimethyl-4-(2-naphthyl)piperidine-3-carboxylate. It has been sold as a designer drug since around 2015.2

HDMP-28 and CFT overlay source ↗

Most of the TMP analogs of HDMP-28 have SERT Ki values in the range >10,000 and so are selective for dopamine and noradrenaline reuptake, with little or no effect on serotonin. HDMP-28 has high affinity to SERT, and so behaves as a triple reuptake inhibitor.3

aEffect of (dl-threo) TMP and analogs on DA and 5-HT Transporters.
Inhibition of specific analogs at displacing CFT from binding to DAT & RTI-55 from binding to SERT
Ar [3H]CFT DAT [3H]DA Uptake [3H]RTI-55 SERT Inhibition by 10 μM D.R. Potency
Ph 83.9 224 ≫10,000 19.6 2.7 1.00
p-F 35.0 142 >10,000 36.9 4.1 3.33
m-Cl 5.1 23.0 >10,000 45.5 4.5 2.42
p-Me 33.0 126 >10,000 45.0 3.8 0.74
p-NH2 34.5 114 ≫10,000 7.9 3.3 2.18
m,p-Cl2 5.3 (2.67)b 7.0 1,064 (>10,000)b 93.3 1.3 7.98
β-Naphthyl 33.9b 11.0c 53.0c 71.6b ND 4.8c
Cocaine 160 404 401 nd 2.5 0.41
aSchweri, et al. (2002);4 bDavies, et al. (2004);5 cDeutsch, et al. (2001).6

D.R. is the discrimination ratio = [3H]DA ÷ [3H]CFT.

A low D.R. indicates more addictive, whereas a high D.R. indicates low propensity for self-administration.

Legality

HDMP-28 is illegal in Switzerland as of December 2015.7

See also

See also

References

References

  1. Lile JA, Wang Z, Woolverton WL, France JE, Gregg TC, Davies HM, et al. (October 2003). "The reinforcing efficacy of psychostimulants in rhesus monkeys: the role of pharmacokinetics and pharmacodynamics". The Journal of Pharmacology and Experimental Therapeutics. 307 (1): 356–66. doi:10.1124/jpet.103.049825. PMID 12954808. S2CID 5654856.
  2. Carlier J, Giorgetti R, Varì MR, Pirani F, Ricci G, Busardò FP (January 2019). "Use of cognitive enhancers: methylphenidate and analogs". European Review for Medical and Pharmacological Sciences. 23 (1): 3–15. doi:10.26355/eurrev_201901_16741. PMID 30657540.
  3. Davies HM, Hopper DW, Hansen T, Liu Q, Childers SR (April 2004). "Synthesis of methylphenidate analogues and their binding affinities at dopamine and serotonin transport sites". Bioorganic & Medicinal Chemistry Letters. 14 (7): 1799–802. doi:10.1016/j.bmcl.2003.12.097. PMID 15026075.
  4. Schweri MM, Deutsch HM, Massey AT, Holtzman SG (May 2002). "Biochemical and behavioral characterization of novel methylphenidate analogs". The Journal of Pharmacology and Experimental Therapeutics. 301 (2): 527–35. doi:10.1124/jpet.301.2.527. PMID 11961053.
  5. Davies HM, Hopper DW, Hansen T, Liu Q, Childers SR (April 2004). "Synthesis of methylphenidate analogues and their binding affinities at dopamine and serotonin transport sites". Bioorganic & Medicinal Chemistry Letters. 14 (7): 1799–802. doi:10.1016/j.bmcl.2003.12.097. PMID 15026075.
  6. Deutsch HM, Ye X, Shi Q, Liu Z, Schweri MM (April 2001). "Synthesis and pharmacology of site specific cocaine abuse treatment agents: a new synthetic methodology for methylphenidate analogs based on the Blaise reaction". European Journal of Medicinal Chemistry. 36 (4): 303–11. doi:10.1016/s0223-5234(01)01230-2. PMID 11461755.
  7. "Verordnung des EDI über die Verzeichnisse der Betäubungsmittel, psychotropen Stoffe, Vorläuferstoffe und Hilfschemikalien" [Ordinance of the Federal Department of Home Affairs on the lists of narcotics, psychotropic substances, precursors and auxiliary chemicals] (in German). Der Bundesrat (The Federal Council).
Further reading

Further reading

  • Muhammed Ajeebsanu M, Subhahar MB, Karakka Kal AK, Philip M, Perwad Z, Karatt TK, et al. (January 2024). "Comprehensive metabolic investigation of dopamine reuptake inhibitor HDMP-28 in equine liver microsomes and Cunninghamella elegans for doping control". Drug Testing and Analysis. 16 (10): 1182–1194. doi:10.1002/dta.3642. PMID 38225724.