Structural Elucidation of Phenylethyl Etonitazene in Seized Powders

doi:10.11938/cjmr20253151

Abstract

Abstract:

The chemical structure of one seized yellow powder sample was elucidated by Fourier transform infrared spectroscopy (FTIR), gas chromatography-mass spectrometry (GC-MS), ultra-performance liquid chromatography-high resolution mass spectrometry (UPLC-HRMS), and nuclear magnetic resonance (NMR). The yellow powder was identified as 2-[2-(4-ethoxyphenyl)ethyl]-N,N-diethyl-5-nitro-1H-benzimidazole-1-ethanamine and was abbreviated as phenylethyl etonitazene. It is a nitazene-type new psychoactive substance (NPS), which has not been controlled in China. The characteristic absorption peaks in IR spectrum and product ions in mass spectra were discussed. The ¹H and ¹³C NMR signals of phenylethyl etonitazene were fully assigned, aided by its two-dimensional NMR data. The information provided herein will assist forensic science laboratories in identifying this compound or other structurally similar substances in their casework.

Key words: new psychoactive substances, nitazenes, phenylethyl etonitazene, nuclear magnetic resonance (NMR), mass spectrometry (MS), infrared absorption spectroscopy (IR), structural elucidation

CLC Number:

O482.5

LIU Yonghong, LIAO Qi, JIAO Ying, SUN Wei, XIAO Lei, JIA Wei, LIU Cuimei. Structural Elucidation of Phenylethyl Etonitazene in Seized Powders[J]. Chinese Journal of Magnetic Resonance, 2025, 42(4): 414-428.

Figures/Tables 16

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Position	δ _C	DEPT	δ _H(J/Hz)	HSQC	¹H -¹H COSY	¹H -¹H TOCSY	¹H -¹³C HMBC
2	160.2	C	/	/	/	/	H-10, H-14, H-15
4	112.3	CH	8.68 (1H, d, 2.1)	+	/	H-6, H-7	C-5, C-6, C-8, C-9
5	132.9	C	/	/	/	/	H-4, H-7
6	122.5	CH	8.51 (1H, dd, 9.1, 2.1)	+	H-7	H-4, H-7	C-4, C-8, C-9
7	114.7	CH	8.29 (1H, d, 9.1)	+	H-6	H-4, H-6	C-4, C-5, C-9
8	136.8	C	/	/	/	/	H-4, H-6, H-10
9	147.6	C	/	/	/	/	H-4, H-6, H-7
10	40.9	CH₂	4.96 (2H, t, 8.3)	+	H-11	H-11	C-2, C-8, C-11
11	50.0	CH₂	3.43 (2H, t, 8.3)	+	H-10	H-10	C-10, C-12a, C-12b
12a	48.8	CH₂	3.36 (4H, m)	+	H-13a	H-13a, H-13b	C-11, C-12b, C-13a
12b	48.8	CH₂	3.36 (4H, m)	+	H-13b	H-13a, H-13b	C-11, C-12a, C-13b
13a	9.1	CH₃	1.39 (6H, t, 7.3)	+	H-12a	H-12a, H-12b	C-12a
13b	9.1	CH₃	1.39 (6H, t, 7.3)	+	H-12b	H-12a, H-12b	C-12b
14	29.7	CH₂	3.65 (2H, t, 7.6)	+	H-15	H-15	C-2, C-15, C-16
15	33.0	CH₂	3.27 (2H, t, 7.6)	+	H-14	H-14	C-2, C-14, C-17a, C-17b
16	131.6	C	/	/	/	/	H-14, H-18a, H-18b
17a	130.7	CH	7.21 (2H, d, 8.6)	+	H-18a	H-18a, H-18b	C-15, C-17b, C-18a, C-19
17b	130.7	CH	7.21 (2H, d, 8.6)	+	H-18b	H-18a, H-18b	C-15, C-17a, C-18b, C-19
18a	116.0	CH	6.85 (2H, d, 8.6)	+	H-17a	H-17a, H-17b	C-16, C-18b, C-19
18b	116.0	CH	6.85 (2H, d, 8.6)	+	H-17b	H-17a, H-17b	C-16, C-18a, C-19
19	159.7	C	/	/	/	/	H-17a, H-17b, H-18a, H-18b, H-20
20	64.5	CH₂	3.98 (2H, q, 7.0)	+	H-21	H-21	C-19, C-21
21	15.1	CH₃	1.35 (3H, t, 7.0)	+	H-20	H-20	C-20