β-Asarone (2, 4, 5-trimethoxy-(Z)-1-propenylbenzene) was obtained from Acorus calamus. Nitration of β-asarone with AgNO2/I2 in ether yielded 1-(2, 4, 5-trimethoxy phenyl)-2-nitropropene (1) but with NaNO2/I2 in ethylene glycol obtained 1-(2, 4, 5-trimethoxy phenyl)-1-nitropropene (2). Compound 2 was prepared for the first time and characterized using IR, 1H-NMR, 13C-NMR, and GC-MS spectra and it was converted into 1-(2, 4, 5-trimethoxy) phenyl-1-propanone (3) using modified Nef reaction. Based on 1D NOESY experiments, compounds 1 and 2 have been assigned E configuration. Compounds 1 and 2 were subjected to cytotoxic activity using five human cancer cell lines, namely, MCF-7, SW-982, HeLa, PC-3, and IMR-32 by MTT assay. Except in breast cancer line (MCF-7) compound 2 exhibited five- to tenfold increase in activity compared to β-asarone and twofold increase over compound 1. 1. Introduction Acorus calamus (Acoraceae) also known as sweet flag in Indian traditional medicine is generally used for treatment of cough, fever, bronchitis, inflammation, depression, tumors, haemorrhoids, skin diseases, insomnia, hysteria, epilepsy, and loss of memory [1, 2]. While β-asarone (2, 4, 5-trimethoxy-(Z)-1-propenylbenzene) was the main constituent (70 to 90%) of rhizomes of Acorus calamus [3], α-asarone (2, 4, 5-trimethoxy-(E)-1-propenylbenzene) was isolated as a minor component (8 to 14%) from the rhizomes of related species Acorus gramineus [4]. Comparative study of genotoxicity and cytotoxicity of β-asarone and α-asarone was investigated and found that α-asarone was more toxic in the HepG2 cell system [5–7]. In continuation of our research on β-asarone, we carried out different chemical conversions to get pharmacologically active compounds [8, 9]. Herein we report the preparation of nitro derivatives of β-asarone and their biological activity. Nitro group is an important functional group because it can be easily converted into many functional groups [10–12]. Psychoactive drugs, namely, amphetamines, are generally prepared by reduction of β-methyl-β-nitrostyrenes [13–16]. Generally nitration of alkenes and substituted styrenes was carried out by metal nitrites using NaNO2/AgNO2 with iodine, NaNO2/H2SO4 in ether (Bruckner’s method), Cu (II)tetrafluoroborate with NaNO2, alkyl halide and metal nitrite (Victor-Meyer reaction), and HgCl2-NaNO2 [17–23]. Formation of nitryl iodide was first reported by Birchenbachin 1932 from AgNO2/I2 [24]. Later on AgNO2 was replaced with less expensive NaNO2/H2O/I2/EtOAc/ethylene glycol or KNO2/18-crown-6/I2/THF [25–27]. 2. Results and
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