Chemical structure of rhynchophylline
IUPAC name
Methyl (7β,16E,20α)-16-(methoxymethylene)-2-oxocorynoxan-17-oate
Preferred IUPAC name
Methyl (2E)-2-[(1′R,6′R,7′S,8a′S)-6′-ethyl-2-oxo-1,2,2′,3′,6′,7′,8′,8a′-octahydro-5′H-spiro[indole-3,1′-indolizin]-7′-yl]-3-methoxyprop-2-enoate
Other names
  • Rhyncophylline
  • Mitrinermin
  • Mitrinermine
  • Rhynchophyllin
  • Rhynocophylline
3D model (JSmol)
ECHA InfoCard 100.208.612 Edit this at Wikidata
  • InChI=1S/C22H28N2O4/c1-4-14-12-24-10-9-22(17-7-5-6-8-18(17)23-21(22)26)19(24)11-15(14)16(13-27-2)20(25)28-3/h5-8,13-15,19H,4,9-12H2,1-3H3,(H,23,26)/b16-13+/t14-,15-,19-,22+/m0/s1
  • InChI=1/C22H28N2O4/c1-4-14-12-24-10-9-22(17-7-5-6-8-18(17)23-21(22)26)19(24)11-15(14)16(13-27-2)20(25)28-3/h5-8,13-15,19H,4,9-12H2,1-3H3,(H,23,26)/b16-13+/t14-,15-,19-,22+/m0/s1
  • CC[C@H]1CN2CC[C@]3([C@@H]2C[C@@H]1/C(=C\OC)/C(=O)OC)C4=CC=CC=C4NC3=O
Molar mass 384.476 g·mol−1
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Rhynchophylline is an alkaloid found in certain Uncaria species (Rubiaceae), notably Uncaria rhynchophylla[1] and Uncaria tomentosa.[2] It also occurs in the leaves of Mitragyna speciosa (kratom),[3] a tree native to Thailand. Chemically, it is related to the alkaloid mitragynine.

Rhynchophylline is a non-competitive NMDA antagonist (IC50 = 43.2 μM) and a calcium channel blocker.[4][5]

Uncaria species have had a variety of uses in traditional herbal medicine, such as for lightheadedness, convulsions, numbness, and hypertension.[6] These uses have been associated with the presence of rhynchophylline and have encouraged its investigation as a drug candidate for several cardiovascular and central nervous system diseases; however, few clinically relevant studies have been conducted.[6]

See also


  1. ^ Shi JS, Yu JX, Chen XP, Xu RX (2003). "Pharmacological Actions of Uncaria Alkaloids, Rhynchophylline and Isorhynchophylline" (PDF). Acta Pharmacologica Sinica. 24 (2): 97–101. PMID 12546715.
  2. ^ Mohamed AF, Matsumoto K, Tabata K, Takayama H, Kitajima M, Watanabe H (2000). "Effects of Uncaria tomentosa Total Alkaloid and its Components on Experimental Amnesia in Mice: Elucidation Using the Passive Avoidance Test". Journal of Pharmacy and Pharmacology. 52 (12): 1553–1561. doi:10.1211/0022357001777612. PMID 11197086. S2CID 40280160.
  3. ^ "Mitragyna Speciosa (Kratom) - World Roots".
  4. ^ Kang TH, Murakami Y, Matsumoto K, Takayama H, Kitajima M, Aimi N, Watanabe H (2002). "Rhynchophylline and Isorhynchophylline Inhibit NMDA Receptors Expressed in Xenopus Oocytes". European Journal of Pharmacology. 455 (1): 27–34. doi:10.1016/S0014-2999(02)02581-5. PMID 12433591.
  5. ^ Kang TH, Murakami Y, Takayama H, Kitajima M, Aimi N, Watanabe H, Matsumoto K (2004). "Protective Effect of Rhynchophylline and Isorhynchophylline on in vitro Ischemia-Induced Neuronal Damage in the Hippocampus: Putative Neurotransmitter Receptors Involved in their Action". Life Sciences. 76 (3): 331–343. doi:10.1016/j.lfs.2004.08.012. PMID 15531384.
  6. ^ a b Zhou J, Zhou S (2010). "Antihypertensive and neuroprotective activities of rhynchophylline: the role of rhynchophylline in neurotransmission and ion channel activity". Journal of Ethnopharmacology. 132 (1): 15–27. doi:10.1016/j.jep.2010.08.041. PMID 20736055.