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organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoIUCrDATA
ISSN: 2414-3146
Volume 6| Part 2| February 2021| x210123
https://doi.org/10.1107/S2414314621001231

Bufotenidinium iodide

CROSSMARK_Color_square_no_text.svg
Duyen N. K. Pham,a Andrew R. Chadeayne,b James A. Golena and David R. Mankea*

aUniversity of Massachusetts Dartmouth, 285 Old Westport Road, North Dartmouth, MA 02747, USA, and bCaaMTech, Inc., 58 East Sunset Way, Suite 209, Issaquah, WA 98027, USA
*Correspondence e-mail: dmanke@umassd.edu

Edited by M. Bolte, Goethe-Universität Frankfurt, Germany (Received 2 February 2021; accepted 2 February 2021; online 5 February 2021)

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].

CCDC reference: 2060560

Similar articles
3D view (loading...)
[Scheme 3D1]
Chemical scheme
[Scheme 1]

Structure description

Bufotenidine, the N,N,N-trimethyl analog of serotonin, was first identified in toad secretions in 1934 (Wieland et al., 1934[Wieland, H., Konz, W. & Mittasch, H. (1934). Justus Liebigs Ann. Chem. 513, 1-25.]). This is one of many indo­alkyl­amines found in the secretions of the Colorado River toad, including bufotenine (5-hy­droxy-N,N-di­methyl­tryptamine), 5-MeO-DMT (5-meth­oxy-N,N-di­methyl­tryptamine), 5-meth­oxy­tryptophol, and bufoviridine. The primary psychedelic in these secretions, 5-MeO-DMT, has been studied individually to treat anxiety and depression (Davis et al., 2019[Davis, A. K., So, S., Lancelotta, R., Barsuglia, J. P. & Griffiths, R. R. (2019). Am. J. Drug Alcohol Abuse, 45, 161-169.]). The inhalation of vaporized dried toad secretions has also been examined in the treatment of depression, anxiety and stress (Uthaug et al., 2019[Uthaug, M. V., Lancelotta, R., van Oorsouw, K., Kuypers, K. P. C., Mason, N., Rak, J., Šuláková, A., Jurok, R., Maryška, M., Kuchař, M., Páleníček, T., Riba, J. & Ramaekers, J. G. (2019). Psychopharmacology, 236, 2653-2666.]). As this area of research continues, it will be important to understand the difference between pure 5-MeO-DMT and natural toad secretions, to understand the significance of each component, and examine if an entour­age effect is present (Bauer, 2020[Bauer, B. E. (2020). Psychedelic Science Review. https://psychedelicreview.com/hamilton-morris-on-5-meo-dmt-the-entourage-effect-and-protecting-toads/]). To this end, we have begun to examine some of the minor components of these secretions, and report the first single-crystal structure of the natural product bufotenidine herein.

In the solid-state structure of bufotenidine iodide, the 5-hy­droxy-N,N,N-tri­methyl­tryptammonium cation and the iodide anion are held together in the asymmetric unit via O—H⋯I hydrogen bonds (Fig. 1[link]). The cation possesses a near planar indole group with a mean deviation from planarity of 0.010 Å. The ethyl­amino group is turned away from the plane with a C1—C8—C9—C10 torsion angle of 92.6 (3)°. The N—H of the indole ring hydrogen bonds with a symmetry generated iodide. The N—H⋯I and O—H⋯I hydrogen bonds (Table 1[link]) link the ions together in infinite chains along the [100] direction with graph-set notation C21(9) (Etter et al., 1990[Etter, M. C., MacDonald, J. C. & Bernstein, J. (1990). Acta Cryst. B46, 256-262.]). The packing of 5-HTQ iodide is shown in Fig. 2[link].

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
N1—H1A⋯I1i 0.85 (1) 2.89 (2) 3.662 (2) 152 (3)
O1—H1⋯I1 0.85 (1) 2.72 (3) 3.468 (2) 147 (4)
Symmetry code: (i) [x-{\script{1\over 2}}, -y+{\script{3\over 2}}, -z+1].
[Figure 1]
Figure 1
The mol­ecular structure of 5-hy­droxy-N,N,N-tri­methyl­tryptammonium (5-HTQ) iodide, showing the atom labeling. Displacement ellipsoids are drawn at the 50% probability level. A hydrogen bond is shown as a dashed line.
[Figure 2]
Figure 2
The crystal packing of 5-hy­droxy-N,N,N-tri­methyl­tryptammonium (5-HTQ) iodide, viewed along the a axis. The hydrogen bonds (Table 1[link]) are shown as dashed lines. Displacement ellipsoids are drawn at the 50% probability level. Hydrogen atoms not involved in hydrogen bonds are omitted for clarity.

The structure of the closely related natural product from toad secretions, bufotenine, 5-hy­droxy-N,N-di­methyl­trypt­amine (BUFTEN: Falkenberg, 1972[Falkenberg, G. (1972). Acta Cryst. B28, 3219-3228.]) has been previously reported. There are only six reported structures of quaternary tryptamines, which are all from the past year. Those are the iodide salts of 4-hy­droxy-N,N,N-tri­methyl­tryptamine (4-HO-TMT) and 4-acet­oxy-N,N,N-tri­methyl­tryptamine (4-AcO-TMT) (XUXFAA and XUXDUS; Chadeayne, Pham, Reid et al., 2020[Chadeayne, A. R., Pham, D. N. K., Reid, B. G., Golen, J. A. & Manke, D. R. (2020). ACS Omega, 5, 16940-16943.]), N,N-dimethyl-N-n-propyl­tryptamine (DMPT) and N,N-dimethyl-N-allyl­tryptamine (DMALT) (CCDC 2017817 and CCDC 2017818; Chadeayne, Pham, Golen & Manke, 2020[Chadeayne, A. R., Pham, D. N. K., Golen, J. A. & Manke, D. R. (2020). Acta Cryst. E76, 1357-1360.]), 5-meth­oxy-2-methyl-N,N,N-tri­methyl­tryptamine (5-MeO-2-Me-TMT) and its hydrate (CCDC 2058144 and CCDC 2058145; Pham et al., 2021[Pham, D. N. K., Chadeayne, A. R., Golen, J. A. & Manke, D. R. (2021). Acta Cryst. E77, 190-194.]).

Synthesis and crystallization

5-Hy­droxy-N,N,N-tri­methyl­tryptammonium iodide was prepared according to literature procedure (Adhikari et al., 2015[Adhikari, B. B., Roshandel, S., Fujii, A. & Schramm, M. P. (2015). Eur. J. Org. Chem. 2015, 2683-2690.]), and crystals suitable for diffraction study were grown from the evaporation of a methanol solution.

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2[link].

Table 2
Experimental details

Crystal data
Chemical formula C13H19N2O+·I−
Mr 346.20
Crystal system, space group Orthorhombic, P212121
Temperature (K) 297
a, b, c (Å) 8.9944 (4), 11.3250 (6), 14.4042 (7)
V (Å3) 1467.23 (12)
Z 4
Radiation type Mo Kα
μ (mm−1) 2.17
Crystal size (mm) 0.25 × 0.19 × 0.18
 
Data collection
Diffractometer Bruker D8 Venture CMOS
Absorption correction Multi-scan (SADABS; Bruker, 2018[Bruker (2018). APEX3, SAINT, and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.])
Tmin, Tmax 0.672, 0.745
No. of measured, independent and observed [I > 2σ(I)] reflections 45268, 2937, 2866
Rint 0.023
(sin θ/λ)max (Å−1) 0.625
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.013, 0.032, 1.08
No. of reflections 2937
No. of parameters 165
No. of restraints 2
H-atom treatment H atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3) 0.42, −0.37
Absolute structure Flack x determined using 1216 quotients [(I+)−(I−)]/[(I+)+(I−)] (Parsons et al., 2013[Parsons, S., Flack, H. D. & Wagner, T. (2013). Acta Cryst. B69, 249-259.])
Absolute structure parameter −0.021 (4)
Computer programs: APEX3 and SAINT (Bruker, 2018[Bruker (2018). APEX3, SAINT, and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]), SHELXT2014 (Sheldrick, 2015b[Sheldrick, G. M. (2015b). Acta Cryst. C71, 3-8.]), SHELXL2018 (Sheldrick, 2015a[Sheldrick, G. M. (2015a). Acta Cryst. A71, 3-8.]), OLEX2 (Dolomanov et al., 2009[Dolomanov, O. V., Bourhis, L. J., Gildea, R. J., Howard, J. A. K. & Puschmann, H. (2009). J. Appl. Cryst. 42, 339-341.]) and publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Structural data

CCDC reference: 2060560

Crystal structure: contains datablock I. DOI: https://doi.org/10.1107/S2414314621001231/bt4107sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314621001231/bt4107Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2414314621001231/bt4107Isup3.cml

checkCIF report


Computing details top

Data collection: APEX3 (Bruker, 2018); cell refinement: SAINT (Bruker, 2018); data reduction: SAINT (Bruker, 2018); program(s) used to solve structure: SHELXT2014 (Sheldrick, 2015b); program(s) used to refine structure: SHELXL2018 (Sheldrick, 2015a); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: publCIF (Westrip, 2010).

[2-(5-Hydroxy-1H-indol-3-yl)ethyl]trimethylazanium iodide top
Crystal data top
C13H19N2O+·I−Dx = 1.567 Mg m−3
Mr = 346.20Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, P212121Cell parameters from 9674 reflections
a = 8.9944 (4) Åθ = 2.7–26.4°
b = 11.3250 (6) ŵ = 2.17 mm−1
c = 14.4042 (7) ÅT = 297 K
V = 1467.23 (12) Å3BLOCK, colourless
Z = 40.25 × 0.19 × 0.18 mm
F(000) = 688
Data collection top
Bruker D8 Venture CMOS
diffractometer		2866 reflections with I > 2σ(I)
φ and ω scansRint = 0.023
Absorption correction: multi-scan
(SADABS; Bruker, 2018)		θmax = 26.4°, θmin = 2.9°
Tmin = 0.672, Tmax = 0.745h = −11→10
45268 measured reflectionsk = −14→14
2937 independent reflectionsl = −18→18
Refinement top
Refinement on F2Primary atom site location: dual
Least-squares matrix: fullHydrogen site location: mixed
R[F2 > 2σ(F2)] = 0.013H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.032 w = 1/[σ2(Fo2) + (0.0105P)2 + 0.4198P]
where P = (Fo2 + 2Fc2)/3
S = 1.08(Δ/σ)max = 0.002
2937 reflectionsΔρmax = 0.42 e Å−3
165 parametersΔρmin = −0.37 e Å−3
2 restraints
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Refinement. The H atoms bonded to C were positioned geometrically and refined using a riding model with C—H = 0.97 Å and Uiso(H) = 1.2Ueq(C) for CH2 and C—H = 0.93 Å and Uiso(H) = 1.2Ueq(C) for CH and with C—H = 0.96 Å and Uiso(H) = 1.5Ueq(C) for CH3. The H atoms bonded to O and N were refined isotropically with a distance restraint of 0.86 (1) Å for O—H and N—H.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
I11.27678 (2)0.68783 (2)0.80214 (2)0.04918 (6)
O10.9362 (3)0.5938 (3)0.71675 (17)0.0750 (7)
N10.6590 (3)0.6055 (2)0.37895 (16)0.0498 (5)
N20.2789 (2)0.30817 (18)0.61774 (13)0.0391 (4)
C10.5215 (3)0.5666 (2)0.40501 (19)0.0485 (6)
H1B0.4414460.5561780.3649480.058*
C20.7484 (3)0.61161 (18)0.45606 (16)0.0406 (6)
C30.8962 (3)0.6469 (2)0.4660 (2)0.0497 (7)
H30.9508710.6731970.4153020.060*
C40.9584 (3)0.6418 (2)0.5530 (2)0.0507 (7)
H41.0565320.6653600.5615010.061*
C50.8756 (3)0.6014 (2)0.6292 (2)0.0479 (6)
C60.7298 (3)0.5668 (2)0.62022 (16)0.0429 (5)
H60.6763250.5403560.6714100.052*
C70.6637 (3)0.57222 (19)0.53238 (16)0.0364 (5)
C80.5182 (3)0.5451 (2)0.49817 (17)0.0391 (5)
C90.3882 (3)0.5012 (2)0.55239 (19)0.0447 (6)
H9A0.2964700.5253100.5224260.054*
H9B0.3898800.5345450.6144140.054*
C100.3953 (3)0.3676 (2)0.55785 (17)0.0358 (5)
H10A0.3869060.3364000.4953640.043*
H10B0.4926110.3456430.5811860.043*
C110.3074 (4)0.3325 (3)0.71866 (17)0.0547 (7)
H11A0.4062030.3074580.7344500.082*
H11B0.2366880.2900830.7557610.082*
H11C0.2976750.4156450.7302850.082*
C120.2907 (3)0.1772 (2)0.6019 (2)0.0566 (6)
H12A0.3889970.1510500.6176560.085*
H12B0.2712150.1600130.5377430.085*
H12C0.2193550.1369970.6400600.085*
C130.1260 (3)0.3483 (3)0.5916 (2)0.0599 (8)
H13A0.1139550.4298320.6080600.090*
H13B0.0536210.3015580.6240090.090*
H13C0.1123050.3390990.5258710.090*
H1A0.686 (4)0.629 (3)0.3256 (13)0.070 (10)*
H11.021 (2)0.625 (3)0.713 (3)0.093 (14)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
I10.04798 (9)0.05760 (10)0.04197 (8)−0.00650 (8)−0.00644 (7)0.00349 (8)
O10.0540 (13)0.118 (2)0.0527 (13)−0.0119 (14)−0.0117 (10)−0.0055 (13)
N10.0669 (15)0.0466 (12)0.0357 (11)−0.0056 (11)0.0020 (11)0.0092 (9)
N20.0353 (8)0.0375 (9)0.0444 (9)−0.0029 (11)0.0023 (8)−0.0056 (8)
C10.0556 (15)0.0419 (13)0.0480 (14)0.0001 (12)−0.0082 (12)0.0017 (12)
C20.0484 (17)0.0282 (10)0.0450 (13)−0.0017 (10)0.0060 (11)0.0012 (9)
C30.0529 (16)0.0398 (13)0.0564 (16)−0.0067 (12)0.0170 (14)0.0026 (12)
C40.0401 (14)0.0433 (13)0.0688 (18)−0.0059 (11)0.0041 (13)−0.0079 (13)
C50.0463 (15)0.0500 (15)0.0473 (14)−0.0004 (12)−0.0031 (12)−0.0097 (11)
C60.0443 (12)0.0455 (12)0.0389 (11)−0.0029 (12)0.0044 (11)−0.0020 (9)
C70.0432 (12)0.0263 (10)0.0396 (12)−0.0014 (9)0.0050 (10)−0.0021 (9)
C80.0441 (13)0.0288 (11)0.0442 (13)−0.0010 (10)−0.0002 (11)−0.0021 (10)
C90.0402 (13)0.0375 (13)0.0564 (16)0.0024 (11)0.0048 (12)−0.0018 (12)
C100.0325 (11)0.0365 (11)0.0385 (12)−0.0011 (9)0.0010 (9)−0.0048 (9)
C110.0672 (19)0.0554 (16)0.0414 (13)−0.0034 (13)0.0083 (11)−0.0036 (11)
C120.0596 (15)0.0380 (12)0.0721 (17)−0.0109 (14)0.0107 (14)−0.0071 (13)
C130.0313 (12)0.069 (2)0.080 (2)−0.0019 (12)0.0037 (14)0.0006 (16)
Geometric parameters (Å, º) top
O1—C51.377 (4)C6—H60.9300
O1—H10.847 (13)C6—C71.399 (3)
N1—C11.366 (4)C7—C81.432 (3)
N1—C21.373 (3)C8—C91.492 (4)
N1—H1A0.849 (13)C9—H9A0.9700
N2—C101.515 (3)C9—H9B0.9700
N2—C111.502 (3)C9—C101.516 (3)
N2—C121.504 (3)C10—H10A0.9700
N2—C131.496 (3)C10—H10B0.9700
C1—H1B0.9300C11—H11A0.9600
C1—C81.364 (4)C11—H11B0.9600
C2—C31.395 (4)C11—H11C0.9600
C2—C71.410 (3)C12—H12A0.9600
C3—H30.9300C12—H12B0.9600
C3—C41.373 (4)C12—H12C0.9600
C4—H40.9300C13—H13A0.9600
C4—C51.403 (4)C13—H13B0.9600
C5—C61.374 (4)C13—H13C0.9600
C5—O1—H1106 (3)C1—C8—C9126.2 (3)
C1—N1—C2108.9 (2)C7—C8—C9127.4 (2)
C1—N1—H1A128 (2)C8—C9—H9A109.9
C2—N1—H1A123 (2)C8—C9—H9B109.9
C11—N2—C10110.56 (19)C8—C9—C10109.0 (2)
C11—N2—C12108.4 (2)H9A—C9—H9B108.3
C12—N2—C10107.63 (18)C10—C9—H9A109.9
C13—N2—C10110.9 (2)C10—C9—H9B109.9
C13—N2—C11110.2 (2)N2—C10—C9116.3 (2)
C13—N2—C12109.0 (2)N2—C10—H10A108.2
N1—C1—H1B124.8N2—C10—H10B108.2
C8—C1—N1110.3 (2)C9—C10—H10A108.2
C8—C1—H1B124.8C9—C10—H10B108.2
N1—C2—C3131.0 (2)H10A—C10—H10B107.4
N1—C2—C7107.4 (2)N2—C11—H11A109.5
C3—C2—C7121.7 (2)N2—C11—H11B109.5
C2—C3—H3121.0N2—C11—H11C109.5
C4—C3—C2118.1 (3)H11A—C11—H11B109.5
C4—C3—H3121.0H11A—C11—H11C109.5
C3—C4—H4119.7H11B—C11—H11C109.5
C3—C4—C5120.7 (3)N2—C12—H12A109.5
C5—C4—H4119.7N2—C12—H12B109.5
O1—C5—C4121.7 (3)N2—C12—H12C109.5
C6—C5—O1116.5 (3)H12A—C12—H12B109.5
C6—C5—C4121.8 (3)H12A—C12—H12C109.5
C5—C6—H6120.7H12B—C12—H12C109.5
C5—C6—C7118.5 (2)N2—C13—H13A109.5
C7—C6—H6120.7N2—C13—H13B109.5
C2—C7—C8107.1 (2)N2—C13—H13C109.5
C6—C7—C2119.3 (2)H13A—C13—H13B109.5
C6—C7—C8133.6 (2)H13A—C13—H13C109.5
C1—C8—C7106.3 (2)H13B—C13—H13C109.5
O1—C5—C6—C7−179.6 (2)C3—C2—C7—C8179.1 (2)
N1—C1—C8—C7−0.1 (3)C3—C4—C5—O1179.0 (3)
N1—C1—C8—C9−179.7 (2)C3—C4—C5—C6−0.7 (4)
N1—C2—C3—C4−178.8 (3)C4—C5—C6—C70.1 (4)
N1—C2—C7—C6178.5 (2)C5—C6—C7—C20.6 (3)
N1—C2—C7—C8−1.5 (3)C5—C6—C7—C8−179.4 (3)
C1—N1—C2—C3−179.3 (3)C6—C7—C8—C1−179.0 (3)
C1—N1—C2—C71.5 (3)C6—C7—C8—C90.6 (4)
C1—C8—C9—C1092.6 (3)C7—C2—C3—C40.4 (4)
C2—N1—C1—C8−0.8 (3)C7—C8—C9—C10−86.9 (3)
C2—C3—C4—C50.4 (4)C8—C9—C10—N2174.8 (2)
C2—C7—C8—C11.0 (3)C11—N2—C10—C9−70.4 (3)
C2—C7—C8—C9−179.4 (2)C12—N2—C10—C9171.4 (2)
C3—C2—C7—C6−0.9 (3)C13—N2—C10—C952.2 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1A···I1i0.85 (1)2.89 (2)3.662 (2)152 (3)
O1—H1···I10.85 (1)2.72 (3)3.468 (2)147 (4)
Symmetry code: (i) x−1/2, −y+3/2, −z+1.
 

Acknowledgements

Financial statements and conflict of inter­est: This study was funded by CaaMTech, Inc. ARC reports an ownership inter­est in CaaMTech, Inc., which owns US and worldwide patent applications, covering new tryptamine compounds, compositions, formulations, novel crystalline forms, and methods of making and using the same.

Funding information

Funding for this research was provided by: National Science Foundation, Directorate for Mathematical and Physical Sciences (grant No. CHE-1429086).

References

First citationAdhikari, B. B., Roshandel, S., Fujii, A. & Schramm, M. P. (2015). Eur. J. Org. Chem. 2015, 2683–2690.  Web of Science CrossRef CAS Google Scholar
 First citationBauer, B. E. (2020). Psychedelic Science Review. https://psychedelicreview.com/hamilton-morris-on-5-meo-dmt-the-entourage-effect-and-protecting-toads/  Google Scholar
 First citationBruker (2018). APEX3, SAINT, and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
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ISSN: 2414-3146
Volume 6| Part 2| February 2021| x210123
https://doi.org/10.1107/S2414314621001231
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