Bis(4-acetoxy-N-ethyl-N-n-propyl-tryptammonium) fumarate-fumaric acid (1/1)

The solid-state structure of the title salt/adduct (systemic name: bis-{[2-(4-acet-yloxy-1H-indol-3-yl)eth-yl](eth-yl)propyl-aza-nium} but-2-enedioate-(E)-butenedioic acid (1/1)), 2C17H25N2O2 +·C4H2O4 2-·C4H4O4, was determined by single-crystal X-ray diffraction. The asymmetric unit consists of a singly protonated tryptammonium cation, one half of a fumarate dianion and one half of a fumaric acid mol-ecule. In the crystal, the ions and mol-ecules are linked together in infinite chains propagating along [001] through a series of N-H⋯O and O-H⋯O hydrogen bonds.

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.

3,5-Lutidine penta-aqua sulfate complexes of first-row transition metals: [M(3,5-lutidine)(H2O)5]SO4, with M = Mn, Co, Ni, and Zn

The reactions of MnSO4·H2O, CoSO4·7H2O, NiSO4·6H2O and ZnSO4·7H2O with 3,5-lutidine (3,5-di-methyl-pyridine) yield crystals of penta-aqua-(3,5-di-methyl-pyridine-κN)manganese(II) sulfate, [Mn(C7H9N)(H2O)5]SO4, (1), penta-aqua-(3,5-di-methyl-pyridine-κN)cobalt(II) sulfate, [Co(C7H9N)(H2O)5]SO4, (2), penta-aqua-(3,5-di-methyl-pyridine-κN)nickel(II) sulfate, [Ni(C7H9N)(H2O)5]SO4, (3), and penta-aqua-(3,5-di-methyl-pyridine-κN)zinc(II) sulfate, [Zn(C7H9N)(H2O)5]SO4, (4), which were characterized by single-crystal X-ray diffraction. The four crystals are isostructural, demonstrating near identical unit-cell parameters and atomic positions. The metal atoms are all octa-hedrally coordinated, with one lutidine ligand and five water ligands. The sulfate dianion hydrogen bonds with the coordinated water mol-ecules of the dicationic metal complex salts, generating infinite three-dimensional networks.

N-Methyl-serotonin hydrogen oxalate

The solid-state structure of N-methyl-serotonin {systematic name: [2-(5-hy-droxy-1H-indol-3-yl)eth-yl](meth-yl)aza-nium hydrogen oxalate}, C₁₁H₁₅N₂O⁺·C₂HO₄ ^-, is reported. The structure possesses a singly protonated N-methylserotonin cation and one hydrogen oxalate anion in the asymmetric unit. In the crystal, the mol-ecules are linked by N-H⋯O and O-H⋯O hydrogen bonds into a three-dimensional network.

Receptor Binding Profiles for Tryptamine Psychedelics and Effects of 4-Propionoxy-N,N-dimethyltryptamine in Mice

Analogues of 4-phosphoryloxy-N,N-dimethyltryptamine (psilocybin) are being sold on recreational drug markets and developed as potential medications for psychedelic-assisted therapies. Many of these tryptamine-based psilocybin analogues produce psychedelic-like effects in rodents and humans primarily by agonist activity at serotonin 2A receptors (5-HT2A). However, the comprehensive pharmacological target profiles for these compounds compared to psilocybin and its active metabolite 4-hydroxy-N,N-dimethyltryptamine (psilocin) are unknown. The present study determined the receptor binding profiles of various tryptamine-based psychedelics structurally related to psilocybin across a broad range of potential targets. Specifically, we examined tryptamine psychedelics with different 4-position (hydroxy, acetoxy, propionoxy) and N,N-dialkyl (dimethyl, methyl-ethyl, diethyl, methyl-propyl, ethyl-propyl, diisopropyl, methyl-allyl, diallyl) substitutions. Further, the psilocybin analogue 4-propionoxy-N,N-dimethyltryptamine (4-PrO-DMT) was administered to mice in experiments measuring head twitch response (HTR), locomotor activity, and body temperature. Overall, the present pharmacological profile screening data show that the tryptamine psychedelics target multiple serotonin receptors, including serotonin 1A receptors (5-HT1A). 4-Acetoxy and 4-propionoxy analogues of 4-hydroxy compounds displayed somewhat weaker binding affinities but similar target profiles across 5-HT receptors and other identified targets. Additionally, differential binding screen profiles were observed with N,N-dialkyl position variations across several non-5-HT receptor targets (i.e., alpha receptors, dopamine receptors, histamine receptors, and serotonin transporters), which could impact in vivo pharmacological effects of the compounds. In mouse experiments, 4-PrO-DMT displayed dose-related psilocybin-like effects to produce 5-HT2A-mediated HTR (0.3-3 mg/kg s.c.) as well as 5-HT1A-mediated hypothermia and hypolocomotion (3-30 mg/kg s.c.). Lastly, our data support a growing body of evidence that the 5-HT2A-mediated HTR induced by tryptamine psychedelics is attenuated by 5-HT1A receptor agonist activity at high doses in mice.

Synthesis and structure of 4-hydroxy-N-isopropyltryptamine (4-HO-NiPT) and its precursors

The title compound, 4-hydroxy-N-isopropyltryptamine (4) or 4-HO-NiPT (systematic name: 3-{2-[(propan-2-yl)amino]ethyl}-1H-indol-4-ol), C13H18N2O, was synthesized in three steps from 4-benzyloxyindole (1) (systematic name: 4-phenoxy-1H-indole), C15H13NO. (1) was treated with oxalyl chloride and isopropylamine to produce N-isopropyl-4-benzyloxy-3-indoleglyoxylamide (2) {systematic name: 2-[4-(benzyloxy)-1H-indol-3-yl]-2-oxo-N-(propan-2-yl)acetamide}, C20H20N2O3. (2) was reduced to generate 4-benzyloxy-N-isopropyltryptamine (3) or 4-HO-NiPT, which was characterized as its chloride salt 4-benzyloxy-N-isopropyltryptammonium chloride (3a) (systematic name: {2-[4-(benzyloxy)-1H-indol-3-yl]ethyl}(propan-2-yl)azanium chloride), C20H25N2O·Cl. Finally the benzyl group of (3) was removed via hydrogenation to generate 4-HO-NiPT. The crystal structures of the title compound and all three synthetic precursors are presented.

Structure-Activity Relationships for Psilocybin, Baeocystin, Aeruginascin, and Related Analogues to Produce Pharmacological Effects in Mice

4-Phosphoryloxy-N,N-dimethyltryptamine (psilocybin) is a naturally occurring tertiary amine found in many mushroom species. Psilocybin is a prodrug for 4-hydroxy-N,N-dimethyltryptamine (psilocin), which induces psychedelic effects via agonist activity at the serotonin (5-HT) 2A receptor (5-HT2A). Several other 4-position ring-substituted tryptamines are present in psilocybin-containing mushrooms, including the secondary amine 4-phosphoryloxy-N-methyltryptamine (baeocystin) and the quaternary ammonium 4-phosphoryloxy-N,N,N-trimethyltryptamine (aeruginascin), but these compounds are not well studied. Here, we investigated the structure-activity relationships for psilocybin, baeocystin, and aeruginascin, as compared to their 4-acetoxy and 4-hydroxy analogues, using in vitro and in vivo methods. Broad receptor screening using radioligand binding assays in transfected cells revealed that secondary and tertiary tryptamines with either 4-acetoxy or 4-hydroxy substitutions display nanomolar affinity for most human 5-HT receptor subtypes tested, including the 5-HT2A and the serotonin 1A receptor (5-HT1A). The same compounds displayed affinity for 5-HT2A and 5-HT1A in mouse brain tissue in vitro and exhibited agonist efficacy in assays examining 5-HT2A-mediated calcium mobilization and β-arrestin 2 recruitment. In mouse experiments, only the tertiary amines psilocin, psilocybin, and 4-acetoxy-N,N-dimethyltryptamine (psilacetin) induced head twitch responses (ED50 0.11-0.29 mg/kg) indicative of psychedelic-like activity. Head twitches were blocked by 5-HT2A antagonist pretreatment, supporting 5-HT2A involvement. Both secondary and tertiary amines decreased body temperature and locomotor activity at higher doses, the effects of which were blocked by 5-HT1A antagonist pretreatment. Across all assays, the pharmacological effects of 4-acetoxy and 4-hydroxy compounds were similar, and these compounds were more potent than their 4-phosphoryloxy counterparts. Importantly, psilacetin appears to be a prodrug for psilocin that displays substantial serotonin receptor activities of its own.

The methanol and ethanol solvates of 4-glutarato-N,N-diisopropyltryptamine

The solid-state structures of two solvated forms of 4-glutarato-N,N-diisopropyltryptamine were determined by single-crystal X-ray diffraction, namely, 5-[(3-{2-[bis(propan-2-yl)azaniumyl]ethyl}-1H-indol-4-yl)oxy]-5-oxopentanoate methanol monosolvate, C21H30N2O4·CH3OH, and the analogous ethanol monosolvate, C21H30N2O4·C2H6O. In both compounds, the 4-glutarato-N,N-diisopropyltryptamine exists as a zwitterion with a protonated tertiary ammonium and a deprotonated glutarato carboxylate. The tryptamine zwitterions and alcohol solvates in both structures combine to produce near identical hydrogen-bonding networks, with N—H...O and O—H...O hydrogen bonds joining the molecules together in two-dimensional networks parallel to the (100) plane.

Synthesis, Structural Characterization, and Pharmacological Activity of Novel Quaternary Salts of 4-Substituted Tryptamines

Aeruginascin (4-phosphoryloxy-N,N,N-trimethyltryptammonium) is an analogue of psilocybin (4-phosphoryloxy-N,N-dimethyltryptamine) that has been identified in several species of psilocybin-containing mushrooms. Our team previously reported the synthesis, structural characterization, and biological activity of the putative metabolite of aeruginascin (4-hydroxy-N,N,N-trimethyltryptammonium; 4-HO-TMT) and its potential prodrug (4-acetoxy-N,N,N-trimethyltryptammonium; 4-AcO-TMT). Here, we report the synthesis, structural characterization, and pharmacological activity of several quaternary tryptammonium analogues of 4-HO-TMT and 4-AcO-TMT, namely, 4-hydroxy-N,N-dimethyl-N-ethyltryptammonium (4-HO-DMET), 4-hydroxy-N,N-dimethyl-N-n-propyltryptammonium (4-HO-DMPT), and 4-hydroxy-N,N-dimethyl-N-isopropyltryptammonium (4-HO-DMiPT), as well as their hypothesized prodrugs 4-acetoxy-N,N-dimethyl-N-ethyltryptammonium (4-AcO-DMET), 4-acetoxy-N,N-dimethyl-N-n-propyltryptammonium (4-AcO-DMPT), and 4-acetoxy-N,N-dimethyl-N-isopropyltryptammonium (4-AcO-DMiPT). Compounds were synthesized using established methods, and structures were characterized by single-crystal X-ray diffraction. Test compounds were screened for in vitro pharmacological activity at a variety of receptors and transporters to determine potential targets of action. None of the compounds exhibited measurable affinity for the serotonin 2A receptor (5-HT2A), but several analogues had low micromolar affinity (K i) for the serotonin 1D receptor (5-HT1D) and serotonin 2B receptor (5-HT2B), where they appeared to be weak partial agonists with low micromolar potencies. Importantly, 4-HO-DMET, 4-HO-DMPT, and 4-HO-DMiPT displayed sub-micromolar affinity for the serotonin transporter (SERT; 370-890 nM). The same 4-hydroxy analogues had low to sub-micromolar potencies (IC50) for inhibition of 5-HT uptake at SERT in transfected cells (3.3-12.3 μM) and rat brain tissue (0.31-3.5 μM). Overall, our results show that quaternary tryptammonium analogues do not target 5-HT2A sites, suggesting the compounds lack psychedelic-like subjective effects. However, certain 4-hydroxy quaternary tryptammonium analogues may provide novel templates for exploring structure-activity relationships for selective actions at SERT.

Genetic survey of Psilocybe natural products

Psilocybe magic mushrooms are best known for their main natural product, psilocybin, and its dephosphorylated congener, the psychedelic metabolite psilocin. Beyond tryptamines, the secondary metabolome of these fungi is poorly understood. The genomes of five species ( P. azurescens , P. cubensis , P. cyanescens , P. mexicana , and P. serbica ) were browsed to understand more profoundly common and species-specific metabolic capacities. The genomic analyses revealed a much greater and yet unexplored metabolic diversity than evident from parallel chemical analyses. P. cyanescens and P. mexicana were identified as aeruginascin producers. Lumichrome and verpacamide A were also detected as Psilocybe metabolites. The observations concerning the potential secondary metabolome of this fungal genus support pharmacological and toxicological efforts to find a rational basis for yet elusive phenomena, such as paralytic effects, attributed to consumption of some magic mushrooms.

The crystal structure of baeocystin

The crystal structure of the ‘magic’ mushroom natural product baeocystin is reported for the first time.

The title compound, baeocystin or 4-phosphor­yloxy-N-methyl­tryptamine {systematic name: 3-[2-(methylazaniumyl)ethyl]-1H-indol-4-yl hydrogen phosphate}, C₁₁H₁₅N₂O₄P, has a single zwitterionic mol­ecule in the asymmetric unit. The mol­ecule has an intra­molecular N—H⋯O hydrogen bond between the ammonium cation and the hydro­phosphate anion. In the crystal, the mol­ecules are linked by N—H⋯O and O—H⋯O hydrogen bonds into a three-dimensional network.

Bis(oxotremorine) fumarate bis(fumaric acid)

In the title mol­ecular salt, 2C₁₂H₁₉N₂O⁺·C₄H₂O₄²⁻·2C₄H₄O₄, the components are held together by N—H⋯O and O—H⋯O hydrogen bonds, forming chains along [001].

The title compound, bis­(oxotremorine) fumarate bis­(fumaric acid) {systematic name: 1-[4-(2-oxopyrrolidin-1-yl)but-2-yn­yl]pyrrolidinium (2E)-but-2-ene­di­o­ate bis­[(2E)-but-2-enedioic acid]}, 2C₁₂H₁₉N₂O⁺·C₄H₂O₄²⁻·2C₄H₄O₄, has a single oxotremorine monocation protonated at the pyrrolidine nitro­gen, one fumaric acid mol­ecule and half of a fumarate dianion in the asymmetric unit. The ions and fumaric acid mol­ecules are held together by N—H⋯O and O–H-⋯O hydrogen bonds in 40-membered rings with graph-set notation R⁶₆(40). The fumarate ions join these rings into infinite chains along [001].

Crystal structure of serotonin

The crystal structure of the free base of the ubiquitous neurotransmitter serotonin is reported for the first time.

The title compound, serotonin or 5-hy­droxy­tryptamine (5-HT) [systematic name: 3-(2-amino­eth­yl)-1H-indol-5-ol], C₁₀H₁₂N₂O, has one mol­ecule in the asymmetric unit. The conformation of the ethyl­amino side chain is gauche–gauche [C_a—C_a—C_m—C_m and C_a—C_m—C_m—N (a = aromatic, m = methyl­ene) torsion angles = −64.2 (3) and −61.9 (2)°, respectively]. In the crystal, the mol­ecules are linked into a three-dimensional network by N—H⋯O and O—H⋯N hydrogen bonds.

A cuboidal [Co4(SO4)4] structure supported by β-picoline ligands. Corrigendum

Corrigendum to Acta Cryst. (2022), E78, 108–110.

In the paper by Park et al. [Acta Cryst. (2022), E78, 108–110], there is an error in the chemical formula in the title.

A cuboidal [Cu4(SO4)4] structure supported by β-picoline ligands

A cobalt sulfate complex supported by β-picoline ligands produces a unique cuboidal tetra­mer.

The solid-state structure of the cobalt–β-picoline–sulfate complex tetra-μ₃-sulfato-tetra­kis­[bis­(3-methyl­pyridine)­cobalt(II)], [Co₄(SO₄)₄(C₆H₇N)₈], is reported. The tetra­meric cobalt cluster contains a cuboidal core comprised of four cobalt(II) cations and four sulfate anions at alternate cube vertices. The cobalt corners are each capped with two β-picoline ligands. The sulfate anions adopt a rare [3.2110] bridging motif, and the cuboidal cluster is unprecedented in coordination chemistry.

The crystalline forms of nine hydrochloride salts of substituted tryptamines

The crystal structures of the hydrochloride salts of nine substituted tryptamines, namely, 1-methyltryptammonium chloride, C₁₁H₁₅N₂⁺·Cl^-, (1), 2-methyl-1-phenyltryptammonium chloride, C₁₇H₁₉N₂⁺·Cl^-, (2), 5-methoxytryptammonium chloride, C₁₁H₁₅N₂O⁺·Cl^-, (3), 5-bromotryptammonium chloride, C₁₀H₁₂BrN₂⁺·Cl^-, (4), 5-chlorotryptammonium chloride, C₁₀H₁₂ClN₂⁺·Cl^-, (5), 5-fluorotryptammonium chloride, C₁₀H₁₂FN₂⁺·Cl^-, (6), 5-methyltryptammonium chloride, C₁₁H₁₅N₂⁺·Cl^-, (7), 6-fluorotryptammonium chloride, C₁₀H₁₂FN₂⁺·Cl^-, (8), and 7-methyltryptammonium chloride, C₁₁H₁₅N₂⁺·Cl^-, (9), are reported. The seven tryptamines with N-H indoles, (3)-(9), show very similar structures, with N-H...Cl hydrogen-bonding networks forming two-dimensional sheets in the crystals. These sheets are combinations of R₄²(8) and R₄²(18) rings, and C₂¹(4) and C₂¹(9) chains. Substitution at the indole N atom reduces the dimensionality of the hydrogen-bonding network, with compounds (1) and (2) demonstrating one-dimensional chains that are a combination of different rings and parallel chains.

5-Meth-oxy-N,N-di-n-propyl-tryptamine (5-MeO-DPT): freebase and fumarate

The solid-state structures of the synthetic psychedelic 5-meth-oxy-N,N-di-n-propyl-tryptamine (5-MeO-DPT) {systematic name: N-[2-(5-meth-oxy-1H-indol-3-yl)eth-yl]-N-propyl-propan-1-amine}, C17H25N2O, and its fumarate salt, bis-(5-meth-oxy-N,N-di-n-propyl-tryptammonium) fumarate (systematic name: bis-{N-[2-(5-meth-oxy-1H-indol-3-yl)eth-yl]-N-propyl-propan-1-aminium} but-2-ene-dio-ate), 2C17H25N2O+·C4H2O4 2-, are reported. The freebase has a single tryptamine mol-ecule in the asymmetric unit. The mol-ecules are linked together by N-H⋯N hydrogen bonds in zigzag chains along the [010] direction. The fumarate salt has a single tryptammonium cation and half of a fumarate dianion in the asymmetric unit. The tryptammonium and fumarate ions are held together in one-dimensional chains by a series of N-H⋯O hydrogen bonds. These chains are combinations of R 4 4(22) rings, and C 2 2(14) and C 4 4(28) parallel chains along [001].

'Foxtrot' fumarate: a water-soluble salt of N,N-di-allyl-5-methoxytryptamine (5-MeO-DALT)

The title compound, bis-(N,N-diallyl-5-meth-oxy-tryptammonium) (5-MeO-DALT) fumarate (systematic name: bis-{N-[2-(5-meth-oxy-1H-indol-3-yl)eth-yl]- N-(prop-2-en-1-yl)prop-2-en-1-aminium} (E)-but-2-enedioate), 2C17H23N2O+·C4H2O4 2-, has a single tryptammonium cation and half of a fumarate dianion in the asymmetric unit. The tryptammonium and fumarate ions are held together in one-dimensional chains by a series of N-H⋯O hydrogen bonds. These chains are combinations of R 4 4(22) rings, and C 2 2(14) and C 4 4(28) parallel chains along [111].

Bufotenidinium iodide

The structure of the natural product bufotenidine is reported as its iodide salt.

The title compound, 5-hy­droxy-N,N,N-tri­methyl­tryptammonium (5-HTQ) iodide {systematic name: [2-(5-hy­droxy-1H-indol-3-yl)eth­yl]tri­methyl­aza­nium iodide}, C₁₃H₁₉N₂O⁺·I⁻, has a single tryptammonium cation and one iodide anion in the asymmetric unit. The ions are held together by N—H⋯I and O—H⋯I hydrogen bonds in infinite chains along [100].

2,5-Di-methyl-bufo-tenine and 2,5-di-methyl-bufo-teni-dine: novel derivatives of natural tryptamines found in Bufo alvarius toads

The solid-state structure of the bufotenine derivative bis-(5-meth-oxy-2,N,N-tri-methyl-tryptammonium) (5-MeO-2-Me-DMT) fumarate (systematic name: bis-{[2-(5-meth-oxy-2-methyl-1H-indol-3-yl)eth-yl]di-methyl-aza-nium} (2E)-but-2-enedioate), 2C14H21N2O+·C4H2O4 2-, the bufotenidine derivative 5-meth-oxy-2,N,N,N-tetra-methyl-tryptammonium (5-MeO-2-Me-TMT) iodide {systematic name: [2-(5-meth-oxy-2-methyl-1H-indol-3-yl)eth-yl]tri-methyl-aza-nium iodide}, C15H23N2O+·I-, and the hydrate of the same {systematic name: [2-(5-meth-oxy-2-methyl-1H-indol-3-yl)eth-yl]tri-methyl-aza-nium iodide monohydrate}, C15H23N2O+·I-·H2O, are reported. The structure of 5-MeO-2-Me-DMT fumarate possesses one tryptammonium cation and a half of a fumarate dianion in the asymmetric unit, linked together by N-H⋯O hydrogen bonds in infinite two-dimensional networks parallel to the (101) plane. The structure of 5-MeO-2-Me-TMT iodide possesses one tryptammonium cation and one iodide anion in the asymmetric unit. The ions are linked via N-H⋯I hydrogen bonds, and indoles are coupled in dimers through π-π inter-actions. The hydrate of 5-MeO-2-Me-TMT iodide possesses one tryptammonium cation, one iodide anion and one water mol-ecule in the asymmetric unit. It shows N-H⋯I and O-H⋯I hydrogen bonds that couple the tryptammonium cations into dimers.

Psilacetin derivatives: fumarate salts of the meth-yl-ethyl, meth-yl-allyl and diallyl variants of the psilocin prodrug

The solid-state structures of the salts of three psilacetin derivatives, namely, 4-acet-oxy-N-eth-yl-N-methyl-tryptammonium (4-AcO-MET) hydro-fumarate {sys-tematic name: [2-(4-acet-yloxy-1H-indol-3-yl)eth-yl](meth-yl)ethyl-aza-nium 3-carb-oxy-prop-2-enoate}, C15H21N2O2 +·C4H3O4 -, 4-acet-oxy-N-allyl-N-methyl-tryptammonium (4-AcO-MALT) hydro-fumarate {systematic name: [2-(4-acet-yl-oxy-1H-indol-3-yl)eth-yl](meth-yl)prop-2-enyl-aza-nium 3-carb-oxy-prop-2-eno-ate}, C16H21N2O2 +·C4H3O4 -, and 4-acet-oxy-N,N-di-allyl-tryptammonium (4-AcO-DALT) fumarate-fumaric acid (1/1) (systematic name: bis-{[2-(4-acet-yloxy-1H-indol-3-yl)eth-yl]diprop-2-enyl-aza-nium} but-2-enedioate-(E)-butenedioic acid (1/1)), 2C18H23N2O2 +·C4H2O4 2-·C4H4O4, are reported. All three salts possess a protonated tryptammonium cation. The 4-AcO-MET and 4-AcO-MALT compounds are charge-balanced by 3-carb-oxy-acrylate (hydro-fumarate) anions. The 4-AcO-DALT complex crystallizes as a two-to-one tryptammonium-to-fumarate salt, which co-crystallizes with a fumaric acid mol-ecule. Each structure is consolidated by N-H⋯O and O-H⋯O hydrogen bonds.

The hydrochloride salt of 4-hydroxy-N,N-di-n-propyltryptamine (4-HO-DPT)

The first single-crystal structure of the hydro­chloride salt of a psilocin analogue, specifically 4-hy­droxy-N,N-di-n-propyl­tryptamine (4-HO-DPT) is reported.

The title compound, 4-hy­droxy-N,N-di-n-propyl­tryptammonium (4-HO-DPT) chloride {systematic name: N-[2-(4-hy­droxy-1H-indol-3-yl)eth­yl]-N-propyl­propan-1-aminium chloride}, C₁₆H₂₅N₂O⁺·Cl⁻, has a singly protonated trypt­ammonium cation and one chloride anion in the asymmetric unit. A series of N—H⋯Cl and O—H⋯Cl hydrogen bonds connect the ions together in ladder chains along [010].

DMT analogues: N-ethyl-N-propyl-tryptamine and N-allyl-N-methytryptamine as their hydro-fumarate salts

The solid-state structures of the hydro-fumarate salts of two N,N-di-alkyl-tryptamines, namely N-ethyl-N-propyl-tryptammonium (EPT) hydro-fumarate {systematic name: [2-(1H-indol-3-yl)eth-yl](meth-yl)propyl-aza-nium 3-carb-oxy-prop-2-enoate}, C15H23N2 +·C4H3O4 -, and N-allyl-N-methyl-tryptammonium (MALT) hydro-fumarate {systematic name: [2-(1H-indol-3-yl)eth-yl](meth-yl)(prop-2-en-1-yl)aza-nium 3-carb-oxy-prop-2-enoate}, C14H19N2 +·C4H3O4 -, are reported. Both compounds possess a protonated tryptammonium cation, and a hydro-fumarate anion in the asymmetric unit. The ethyl group of the EPT cation is modeled as a two-component disorder with 50% occupancy for each component. In the extended structure, N-H⋯O and O-H⋯O hydrogen bonds generate infinite two-dimensional networks parallel to the (001) plane for both compounds.

Quaternary tryptammonium salts: N,N-dimethyl-N-n-propyl-tryptammonium (DMPT) iodide and N-allyl-N,N-di-methyl-tryptammonium (DMALT) iodide

The solid-state structures of two quaternary trytpammonium salts, namely, N,N-dimethyl-N-n-propyl-tryptammonium (DMPT) iodide [systematic name: 2-(1H-indol-3-yl)-N,N-dimethyl-N-propyl-aza-nium iodide], C15H23N2 +·I-, and N-allyl-N,N-di-methyl-tryptammonium (DMALT) iodide, [systematic name: 2-(1H-indol-3-yl)-N,N-dimethyl-N-(prop-2-en-1-yl)aza-nium iodide], C15H21N2 +·I-, are reported. Both salts possess a tri-alkyl-tryptammonium cation and an iodide anion in the asymmetric unit, which are joined together through N-H⋯I inter-actions. The DMALT structure was refined as an inversion twin, and the allyl group is disordered over two orientations with a 0.70 (4):0.30 (4) ratio.

Active Metabolite of Aeruginascin (4-Hydroxy-N,N,N-trimethyltryptamine): Synthesis, Structure, and Serotonergic Binding Affinity

The putative active metabolite of aeruginascin, a naturally occurring tryptamine of "magic mushrooms," has been synthesized and structurally characterized. Competitive radioligand binding assays demonstrate that it has a high affinity at human serotonin receptors 5-HT_1A, 5-HT_2A, and 5-HT_2B, though it does not bind at the 5-HT₃ receptor, where activity was previously predicted.

5-MeO-DALT: the freebase of N,N-diallyl-5-methoxytryptamine

The solid-state structure of the synthetic psychedelic 5-meth­oxy-N,N-di­allyl­tryptamine (5-MeO-DMT) is reported in its freebase form.

The title compound {systematic name: N-[2-(5-meth­oxy-1H-indol-3-yl)eth­yl]-N-(prop-2-en-1-yl)prop-2-en-1-amine), C₁₇H₂₂N₂O, has a single tryptamine mol­ecule in the asymmetric unit. The mol­ecules are linked by strong N—H⋯N hydrogen bonds into zigzag chains with graph-set notation C(7) along the [010] direction.

Norpsilocin: freebase and fumarate salt

The solid-state structures of the naturally occurring psychoactive tryptamine norpsilocin {4-hy-droxy-N-methyl-tryptamine (4-HO-NMT); systematic name: 3-[2-(methyl-amino)-eth-yl]-1H-indol-4-ol}, C11H14N2O, and its fumarate salt (4-hy-droxy-N-methyl-tryptammonium fumarate; systematic name: bis-{[2-(4-hy-droxy-1H-indol-3-yl)eth-yl]methyl-aza-nium} but-2-enedioate), C11H15N2O+·0.5C4H2O4 2-, are reported. The freebase of 4-HO-NMT has a single mol-ecule in the asymmetric unit joined together by N-H⋯O and O-H⋯O hydrogen bonds in a two-dimensional network parallel to the (100) plane. The ethyl-amine arm of the tryptamine is modeled as a two-component disorder with a 0.895 (3) to 0.105 (3) occupancy ratio. The fumarate salt of 4-HO-NMT crystallizes with a tryptammonium cation and one half of a fumarate dianion in the asymmetric unit. The ions are joined together by N-H⋯O and O-H⋯O hydrogen bonds to form a three-dimensional framework, as well as π-π stacking between the six-membered rings of inversion-related indoles (symmetry operation: 2 - x, 1 - y, 2 - z).

Bis(4-hy-droxy-N-isopropyl-N-methyl-trypt-ammo-nium) fumarate: a new crystalline form of miprocin

The title compound, bis-(4-hy-droxy-N-isopropyl-N-methyl-tryptammonium) (4-HO-MiPT) fumarate (systematic name: bis-{[2-(4-hy-droxy-1H-indol-3-yl)eth-yl](meth-yl)propan-2-yl-aza-nium} but-2-enedioate), 2C14H21N2O+·C4H2O4 2-, has a singly protonated tryptammonium cation and one half of a fumarate dianion in the asymmetric unit. The tryptammonium and fumarate ions are held together in one-dimensional chains by N-H⋯O and O-H⋯O hydrogen bonds. These chains are a combination of R 4 2(20) rings, and C 2 2(15) and C 4 4(30) parallel chains along (110). They are further consolidated by N-H⋯π inter-actions. There are two two-component types of disorder impacting the tryptammonium fragment with a 0.753 (7):0.247 (7) occupancy ratio and one of the fumarate oxygen atoms with a 0.73 (8):0.27 (8) ratio.

The varied structures of cobalt(II)-pyridine (py)-sulfate: [Co(SO4)(py)4] n , [Co2(SO4)2(py)6] n , and [Co3(SO4)3(py)11] n

The solid-state structures of two cobalt-pyridine-sulfate compounds, namely catena-poly[[tetra-kis-(pyridine-κN)cobalt(II)]-μ-sulfato-κ2 O:O'], [Co(SO4)(C5H5N)4] n , (1), and catena-poly[[tetra-kis-(pyridine-κN)cobalt(II)]-μ-sulfato-κ3 O:O',O''-[bis-(pyridine-κN)cobalt(II)]-μ-sulfato-κ3 O,O':O''] n , [Co2(SO4)2(C5H5N)6] n , (2), are reported. Compound (1) displays a polymeric structure, with infinite chains of CoII cations adopting octa-hedral N4O2 coordination environments that involve four pyridine ligands and two bridging sulfate ions. Compound (2) is also polymeric with infinite chains of CoII cations. The first Co center has an octa-hedral N4O2 coordination environment that involves four pyridine ligands and two bridging sulfate ligands. The second Co center has an octa-hedral N2O4 coordination environment that involves two pyridine ligands and two bridging sulfate ions that chelate the Co atom. The structure of (2) was refined as a two-component inversion twin.

Bis(4-hydroxy-N,N-di-n-propyltryptammonium) fumarate tetrahydrate

The title compound (systematic name: bis{[2-(4-hydroxy-1H-indol-3-yl)ethyl]bis(propan-2-yl)azanium} but-2-enedioate tetrahydrate), 2C16H25N2O+·C4H2O4 2−·4H2O, has a singly protonated DPT cation, one half of a fumarate dianion (completed by a crystallographic centre of symmetry) and two water molecules of crystallization in the asymmetric unit. A series of N—H...O and O—H...O hydrogen bonds form a three-dimensional network in the solid state.

The fumarate salts of the N-isopropyl-N-methyl derivatives of DMT and psilocin

The solid-state structures of the salts of two substituted tryptamines, namely N-isopropyl-N-methyl-tryptaminium (MiPT) fumarate {systematic name: [2-(1H-indol-3-yl)eth-yl](meth-yl)propan-2-yl-aza-nium 3-carb-oxy-prop-2-enoate}, C14H21N2 +·C4H3O4 -, and 4-hy-droxy-N-isopropyl-N-methyl-tryptaminium (4-HO-MiPT) fumarate monohydrate {systematic name: [2-(4-hy-droxy-1H-indol-3-yl)eth-yl](meth-yl)propan-2-yl-aza-nium 3-carb-oxy-prop-2-enoate monohydrate}, C14H21N2O+·C4H3O4 -·H2O, are reported. Both salts possess a proton-ated tryptammonium cation and a 3-carb-oxy-acrylate (hydrogen fumarate) anion in the asymmetric unit; the 4-HO-MiPT structure also contains a water mol-ecule of crystallization. Both cations feature disorder of the side chain over two orientations, in a 0.630 (3):0.370 (3) ratio for MiPT and a 0.775 (5):0.225 (5) ratio for 4-HO-MiPT. In both extended structures, N-H⋯O and O-H⋯O hydrogen bonds generate infinite two-dimensional networks.

N-Methyl-N-propyltryptamine (MPT)

The title compound {systematic name: [2-(1H-indol-3-yl)ethyl](methyl)propylamine}, C14H20N2, has a single molecule in the asymmetric unit. The molecules in the unit cell are held together in infinite one-dimensional chains along [010] through N—H...N hydrogen bonds between indole H atoms and trialkylamine N atoms.

Bis(4-acet-oxy-N,N-di-methyl-tryptammonium) fumarate: a new crystalline form of psilacetin, an alternative to psilocybin as a psilocin prodrug

The title compound has a single protonated psilacetin cation and one half of a fumarate dianion in the asymmetric unit. The ions are held together through N—H⋯O hydrogen bonds in infinite one-dimensional chains along [111].

The title compound (systematic name: bis­{2-[4-(acet­yloxy)-1H-indol-3-yl]ethan-1-aminium} but-2-enedioate), 2C₁₄H₁₉N₂O₂⁺·C₄H₂O₄²⁻, has a single protonated psilacetin cation and one half of a fumarate dianion in the asymmetric unit. There are N—H⋯O hydrogen bonds between the ammonium H atoms and the fumarate O atoms, as well as N—H⋯O hydrogen bonds between the indole H atoms and the fumarate O atoms. The hydrogen bonds hold the ions together in infinite one-dimensional chains along [111].

More crystal field theory in action: the metal-4-picoline (pic)-sulfate [M(pic)x]SO4 complexes (M = Fe, Co, Ni, Cu, Zn, and Cd)

Seven crystal structures of five first-row (Fe, Co, Ni, Cu, and Zn) and one second-row (Cd) transition metal-4-picoline (pic)-sulfate complexes of the form [M(pic)_x]SO₄ are reported. These complexes are catena-poly[[tetrakis(4-methylpyridine-κN)metal(II)]-μ-sulfato-κ²O:O'], [M(SO₄)(C₆H₇N)₄]_n, where the metal/M is iron, cobalt, nickel, and cadmium, di-μ-sulfato-κ⁴O:O-bis[tris(4-methylpyridine-κN)copper(II)], [Cu₂(SO₄)₂(C₆H₇N)₆], catena-poly[[bis(4-methylpyridine-κN)zinc(II)]-μ-sulfato-κ²O:O'], [Zn(SO₄)(C₆H₇N)₂]_n, and catena-poly[[tris(4-methylpyridine-κN)zinc(II)]-μ-sulfato-κ²O:O'], [Zn(SO₄)(C₆H₇N)₃]_n. The Fe, Co, Ni, and Cd compounds are isomorphous, displaying polymeric crystal structures with infinite chains of M^II ions adopting an octahedral N₄O₂ coordination environment that involves four picoline ligands and two bridging sulfate anions. The Cu compound features a dimeric crystal structure, with the Cu^II ions possessing square-pyramidal N₃O₂ coordination environments that contain three picoline ligands and two bridging sulfate anions. Zinc crystallizes in two forms, one exhibiting a polymeric crystal structure with infinite chains of Zn^II ions adopting a tetrahedral N₂O₂ coordination containing two picoline ligands and two bridging sulfate anions, and the other exhibiting a polymeric crystal structure with infinite chains of Zn^II ions adopting a trigonal bipyramidal N₃O₂ coordination containing three picoline ligands and two bridging sulfate anions. The structures are compared with the analogous pyridine complexes, and the observed coordination environments are examined in relation to crystal field theory.

Designing crystalline, flexible covalent metal–organic networks through controlled ligand deprotection

Our lab has developed a synthetic approach to control the growth of crystalline covalent metal–organic networks through a base-mediated deprotection of the organic linkers.

The crystal structures of iron and cobalt pyridine (py)-sulfates, [Fe(SO4)(py)4] n and [Co3(SO4)3(py)11] n

The solid-state structures of two metal-pyridine-sulfate compounds, namely catena-poly[[tetra-kis-(pyridine-κN)iron(II)]-μ-sulfato-κ2O:O'], [Fe(SO4)(C5H5N)4] n , (1), and catena-poly[[tetra-kis-(pyridine-κN)cobalt(II)]-μ-sulfato-κ2O:O'-[tetra-kis-(pyridine-κN)cobalt(II)]-μ-sulfato-κ3O,O':O''-[tris-(pyridine-κN)cobalt(II)]-μ-sulfato-κ2O:O'], [Co3(SO4)3(C5H5N)11] n , (2), are reported. The iron compound (1) displays a polymeric structure, with infinite chains of FeII atoms adopting octa-hedral N4O2 coordination environments that involve four pyridine ligands and two bridging sulfate ligands. The cobalt compound (2) displays a polymeric structure, with infinite chains of CoII atoms. Two of the three Co centers have an octa-hedral N4O2 coordination environment that involves four pyridine ligands and two bridging sulfate ligands. The third Co center has an octa-hedral N3O3 coordination environment that involves three pyridine ligands, and two bridging sulfate ligands with one sulfate chelating the cobalt atom.

First-row transition metal-pyridine (py)-sulfate [(py)xM](SO4) complexes (M = Ni, Cu and Zn): crystal field theory in action

The crystal structures of three first-row transition metal-pyridine-sulfate complexes, namely catena-poly[[tetrakis(pyridine-κN)nickel(II)]-μ-sulfato-κ²O:O'], [Ni(SO₄)(C₅H₅N)₄]_n, (1), di-μ-sulfato-κ⁴O:O-bis[tris(pyridine-κN)copper(II)], [Cu₂(SO₄)₂(C₅H₅N)₆], (2), and catena-poly[[tetrakis(pyridine-κN)zinc(II)]-μ-sulfato-κ²O:O'-[bis(pyridine-κN)zinc(II)]-μ-sulfato-κ²O:O'], [Zn₂(SO₄)₂(C₅H₅N)₆]_n, (3), are reported. Ni compound (1) displays a polymeric crystal structure, with infinite chains of Ni^II atoms adopting an octahedral N₄O₂ coordination environment that involves four pyridine ligands and two bridging sulfate ligands. Cu compound (2) features a dimeric molecular structure, with the Cu^II atoms possessing square-pyramidal N₃O₂ coordination environments that contain three pyridine ligands and two bridging sulfate ligands. Zn compound (3) exhibits a polymeric crystal structure of infinite chains, with two alternating zinc coordination environments, i.e. octahedral N₄O₂ coordination involving four pyridine ligands and two bridging sulfate ligands, and tetrahedral N₂O₂ coordination containing two pyridine ligands and two bridging sulfate ligands. The observed coordination environments are consistent with those predicted by crystal field theory.

The first-row transition-metal series of tris(ethylenediamine) diacetate complexes [M(en)3](OAc)2 (M is Mn, Fe, Co, Ni, Cu, and Zn)

The crystal structures of the first-row transition-metal series of tris(ethylenediamine-κ²N,N')metal(II) diacetate, [M(C₂H₈N₂)₃](CH₃CO₂)₂, with M = Mn, Fe, Co, Ni, Cu, and Zn, are reported. The complexes are all isostructural, crystallizing in a centrosymmetric triclinic cell and possessing an asymmetric unit composed of one [M(en)₃]²⁺ cation and two symmetrically independent acetate anions. In the unit cell, the two complex cations are inversion-generated enantiomers, possessing the energetically favoured Δ(λλλ) and Λ(δδδ) configurations. The complex cations and acetate anions combine through a series of N-H...O hydrogen bonds to generate a three-dimensional network in the crystals. The other notable feature of the series is a significant Jahn-Teller distortion for the d⁹ Cu²⁺ complex.

5,7-Dimethyl-1H-indole-2,3-dione

The title compound, C10H9NO2, crystallizes with four molecules in the asymmetric unit. The molecules are all near planar, with the non-H atoms possessing mean deviations from planarity of 0.017, 0.026, 0.020 and 0.007 Å. In the crystal, the molecules form two dimers, each linked by a pair of N—H...O hydrogen bonds.

7-Methyl-1H-indole-2,3-dione

The title compound, C9H7NO2, has a single molecule in the asymmetric unit, with the non-H atoms possessing a mean deviation from planarity of 0.034 Å. In the crystal, the molecules dimerize through pairs of N—H...O hydrogen bonds. The nine-membered rings of the isatins stack along the b axis, through parallel slipped π–π interactions [intercentroid distance = 3.8832 (4) Å, interplanar distance = 3.4038 (7) Å and slippage = 1.8690 (12) Å].

5,6-Dibromo-1H-indole-2,3-dione

The title compound, C8H3Br2NO2, crystallizes with two near planar molecules in the asymmetric unit, with non-H atoms possessing mean deviations from planarity of 0.012 and 0.014 Å. The two molecules are connected by an N—H...O and a C—H...O hydrogen bond. In the crystal, molecules connect through a series of bifurcated N—(H,H)...O hydrogen bonds, forming chains propagating along the [1-1-1] direction. The molecules are further linked through intermolecular halogen interactions, including a Br...O close contact of 2.9409 (3) Å, and two C—H...Br interactions of 3.777 (3) and 3.845 (3) Å. These interactions link the chains into sheets lying parallel to the (1-23) plane.