N-(4-Hy-droxy-2-nitro-phen-yl)acetamide.

James E Hines Iii,Rao M Uppu,Frank R Fronczek,Curtistine J Deere

doi:10.1107/s2414314622002012

Abstract

The title compound, C8H8N2O4, differs in its degree of planarity from the 3-nitro isomer and also in its hydrogen-bonding pattern. Its NH group forms an intra-molecular hydrogen bond to a nitro oxygen atom, and its OH group forms an inter-molecular hydrogen bond to an amide oxygen atom, generating [10] chains in the crystal.

Highlights

Structure description The putative free-radical products of the peroxynitrite anion (PN)—CO2 reaction (.NO2 and CO3.–) have long been thought to constitute an important source of non-CYP450mediated oxidative biotransformation of N-(4-hydroxyphenyl)acetamide (4-HPA; acetaminophen or paracetamol) and other xenobiotics (Babu et al, 2012; Dou et al, 2017; Gernapudi et al, 2009; Rangan et al, 2006; Uppu et al, 2005)
In reactions of 4-HPA/PN/ CO2, we find that N-(4-hydroxy-3-nitrophenyl)acetamide is one of the major products formed along with N,N0-(6,60-dihydroxy[1,10-biphenyl]-3,30-diyl)bisacetamide and a metastable N-acetyl-1,4-benzoquinone (NBQI; demonstrated through its binding to N-acetyl-l-cysteine; Uppu & Martin, 2005; Deere et al, 2022)
It was shown that NBQI can react with electrophiles such as the nitrite ion and form yet another nitro product, N-(4-hydroxy-2-nitrophenyl)acetamide (Matsuno et al, 1989)

Summary

DÁ Á ÁA

Cantly different degrees of molecular planarity in the solidstate and differ in their hydrogen bonding patterns. In N-(4-hydroxy-2-nitrophenyl)acetamide, Fig. 1, the molecule is nearly planar, with an r.m.s. deviation of 0.035 Afor the non-hydrogen atoms. The N—H group forms an intramolecular hydrogen bond (Table 1) to O3 (part of the nitro group) having an NÁ Á ÁO distance of 2.6363 (15) Aand N—HÁ Á ÁO angle of 139.6 (15). The crystal structure of N-(4-hydroxy-3-nitrophenyl)acetamide has been reported (Salahifar et al, 2015; Deere et al, 2019). It is significantly less planar than the title compound, with the acetamido group twisted out of the plane of the phenyl group by 9.0 (2) and the nitro group twisted out of the phenyl plane by 11.8 (2). Its hydrogen-bonding pattern differs, with the N—H group forming an intermolecular hydrogen bond to the acetamido O atom [NÁ Á ÁO =.

Synthesis and crystallization

Funding information

Bruker Kappa APEXII DUO CCD

Crystal data

Bruker Kappa APEXII DUO CCD diffractometer

Special details