5-Alkyltryptamine derivatives as highly selective and potent 5-HT1D receptor agonists

N-Cyclo-hexyl-tryptamine: freebase, bromide and fumarate

The solid-state structures of N-cyclo-hexyl-tryptamine (I) {systematic name: N-[2-(1H-indol-3-yl)eth-yl]cyclo-hexa-namine}, C16H22N2, and two of its salts, N-cyclo-hexyl-tryptammonium bromide (II) {systematic name: N-[2-(1H-indol-3-yl)eth-yl]cyclo-hexa-naminium bromide}, C16H23N2 +·Br-, and N-cyclo-hexyl-tryptammonium fumarate (III) (systematic name: bis-{N-[2-(1H-indol-3-yl)eth-yl]cyclo-hexa-naminium} (2E)-but-2-enedioate), 2C16H23N2 +·C4H2O4 2-, were determined by single-crystal X-ray diffraction. The freebase compound forms infinite chains along [010] through N-H⋯N hydrogen bonds. The bromide salt is held together by N-H⋯Br inter-actions in two-dimensional sheets along (001). The fumarate salt is held together in infinite three-dimensional frameworks by N-H⋯O hydrogen bonds.

N-Alkylation of phenethylamine and tryptamine

A clean and efficient method for the N-alkylation of tryptamine and phenethylamine, employing alcohols as the alkylating agents, has been developed. The reaction proceeds via catalytic electronic activation, involving an iridium catalyst which activates the alcohol by borrowing hydrogen from the substrate, returning it later in the catalytic cycle. Some examples of N-heterocyclisation have been performed employing a diol as the substrate.

3-(2-Pyrrolidin-1-ylethyl)-5-(1,2,3,6-tetrahydropyridin-4-yl)-1H-indole derivatives as high affinity human 5-HT1B/1D ligands

A series of 3-(2-pyrrolidin-1-ylethyl)-5-(1,2,3,6-tetrahydropyridin-4-yl)-1H-indole derivatives (2) has been prepared using parallel synthesis techniques, and their structure-activity relationships studied. High affinity human 5-HT(1B/1D) (h5-HT(1B/1D)) ligands have been identified.

Design, synthesis and biological activity of novel dimethyl-{2-[6-substituted-indol-1-yl]-ethyl}-amine as potent, selective, and orally-Bioavailable 5-HT 1D agonists

A novel series of highly potent human 5-HT(1D) agonists, dimethyl-[2-[6-substituted-indol-1-yl]-ethyl]-amine, was synthesized. Structure-activity relationship (SAR) investigation revealed 4-[1-(2-dimethylamino-ethyl)-1H-indol-6-yl]-tetrahydro-thiopyran-4-ol, 11b (ALX-2732), as a potent (K(i)=2.4 nM) agonist at the human 5-HT(1D) receptor with good selectivity over the other serotonin receptor subtypes. This compound demonstrated favorable in vitro metabolic stability in human and rat liver microsomes and was found to be orally bioavailable in rats (F(po)=51%).

( R )-3-( N -Methylpyrrolidin-2-ylmethyl)-5-(1,2,3,6-tetrahydropyridin-4-yl)-1H-indole derivatives as high affinity h5-HT 1B/1D ligands

A series of (R)-3-(N-methylpyrrolidin-2-ylmethyl)-5-(1,2,3,6-tetrahydropyridin-4-yl)-1H-indole derivatives (2) have been prepared using parallel synthesis, and their structure-activity relationship studied. High affinity human 5-HT(1B/1D) (h5-HT(1B/1D)) ligands have been identified.

A versatile linkage strategy for solid-phase synthesis of N,N-dimethyltryptamines and beta-carbolines

Various tryptamines are captured by a vinylsulfonylmethyl polystyrene resin, generating a safety-catch linkage. Beta-carbolines can be formed from 4 by a Pictet-Spengler reaction with the introduction of R(1). Tryptamine 4 can also be derivatized by acylation or copper-mediated coupling to introduce R(2). If X = Br, Suzuki coupling can be used to introduce R(3). After derivatization, the indole derivatives are activated with methyl iodide and released under mild basic condition. [reaction: see text]

Acute treatments: some blind alleys

The introduction of sumatriptan, a selective 5-HT(1B/1D) agonist, for the treatment of migraine sparked a new era of drug research in this field. Many novel targets have since been developed, and tested in the clinic. The promise of these approaches is to deliver an anti-migraine compound with the optimal efficacy and safety profile. In this chapter, blind alleys in anti-migraine development are discussed. The failing soldiers have included the NK-1 antagonists, some second-generation 5-HT(1B/1D) agonists, CP-122,288, 4991W93, the neurosteroid ganaxolone, selective 5-HT(1F) (LY334370) and 5-HT(1D) agonists (PNU-142,633), and the endothelin-1 antagonist bosentan. Some of these promising targets failed to demonstrate clinical efficacy, while others were stopped for preclinical toxicity.

MOLECULES

Monitor provides an insight into the latest developments in drug discovery through brief synopses of recent presentations and publications together with expert commentaries on the latest technologies. There are two sections: Molecules summarizes the chemistry and the pharmacological significance and biological relevance of new molecules reported in the literature and on the conference scene; Profiles offers commentary on promising lines of research, emerging molecular targets, novel technology, advances in synthetic and separation techniques and legislative issues.