Tripitramine

Not to be confused with Trimipramine or Tryptamine.

Tripitramine, or tripitamine, is an antimuscarinic drug which was never marketed.^[1][2][3][4]

Tripitramine

Clinical data
Other names	Tripitamine
Drug class	Muscarinic acetylcholine receptor antagonist; Selective muscarinic acetylcholine M2 receptor antagonist
Identifiers
IUPAC name 11-[2-[6-[8-[6-[bis[2-oxo-2-(6-oxo-5H-pyrido[2,3-b][1,4]benzodiazepin-11-yl)ethyl]amino]hexyl-methylamino]octyl-methylamino]hexylamino]acetyl]-5H-pyrido[2,3-b][1,4]benzodiazepin-6-one
CAS Number	152429-64-6
PubChem CID	132947
IUPHAR/BPS	361
ChemSpider	117328
ChEMBL	ChEMBL265256
CompTox Dashboard (EPA)	DTXSID30165030
Chemical and physical data
Formula	C64H77N13O6
Molar mass	1124.405 g·mol−1
3D model (JSmol)	Interactive image
SMILES CN(CCCCCCCCN(C)CCCCCCN(CC(=O)N1C2=CC=CC=C2C(=O)NC3=C1N=CC=C3)CC(=O)N4C5=CC=CC=C5C(=O)NC6=C4N=CC=C6)CCCCCCNCC(=O)N7C8=CC=CC=C8C(=O)NC9=C7N=CC=C9
InChI InChI=1S/C64H77N13O6/c1-72(41-20-8-5-17-35-65-44-56(78)75-53-32-14-11-26-47(53)62(81)69-50-29-23-36-66-59(50)75)39-18-6-3-4-7-19-40-73(2)42-21-9-10-22-43-74(45-57(79)76-54-33-15-12-27-48(54)63(82)70-51-30-24-37-67-60(51)76)46-58(80)77-55-34-16-13-28-49(55)64(83)71-52-31-25-38-68-61(52)77/h11-16,23-34,36-38,65H,3-10,17-22,35,39-46H2,1-2H3,(H,69,81)(H,70,82)(H,71,83) Key:YUJOQEAGGUIMED-UHFFFAOYSA-N

Pharmacology

The drug is a selective antagonist of the muscarinic acetylcholine M₂ receptor.^{[1][2][3][5][6]} Its affinities (K_i) for the muscarinic acetylcholine receptors are 0.27 nM for the M₂ receptor, 1.58 nM for the M₁ receptor (5.9-fold less than for M₂), 6.41 nM for the M₄ receptor (24-fold less than for M₂), 33.87 nM for the M₅ receptor (125-fold less than for M₂), and 38.25 nM for the M₃ receptor (142-fold less than for M₂).^[2][5] Tripitramine has been found to be cardioselective and to increase heart rate in animals.^[1][7]

Chemistry

Structurally, it consists of three pirenzepine- or AQ-RA 741-like tricyclic (more specifically pyridobenzodiazepine) moieties bound together by a long amine-containing hydrocarbon chain similar to the one found within methoctramine (a modestly M₂-selective antimuscarinic agent).^[1][8][4] Related compounds with analogous structural designs include dipitramine, spirotramine, caproctamine, and benextramine, among others.^[1]

History

Tripitramine was first described in the scientific literature by 1993.^[4] It was developed in efforts to discover more highly selective M₂ receptor antagonists than methoctramine.^[1][4]