Study of Complex Nitrogen and Oxygen-bearing Molecules toward the High-mass Protostar IRAS 18089-1732

The observation of oxygen (O)- and nitrogen (N)-bearing molecules gives an idea about the complex prebiotic chemistry in the interstellar medium (ISM). In this article, we present the identification of the rotational emission lines of N-bearing molecules ethyl cyanide (C_2H_5CN), cyanoacetylene (HC_3N), and O-bearing molecules methyl formate (CH_3OCHO) towards high-mass protostar IRAS 18089-1732 using the Atacama Compact Array (ACA). We also detected the emission lines of both N- and O-bearing molecule formamide (NH_2CHO) in the envelope of IRAS 18089-1732. We have detected the v = 0 and 1 states rotational emission lines of CH_3OCHO. We also detected the two vibrationally excited states of HC_3N (v7 = 1 and v7 = 2). The estimated fractional abundances of C_2H_5CN, HC_3N (v7 = 1), HC_3N (v7 = 2), and NH_2CHO towards the IRAS 18089-1732 are (1.40±0.5)×10^-10, (7.5±0.7)×10^-11, (3.1±0.4)×10^-11, and (6.25±0.82)×10^-11. Similarly, the estimated fractional abundances of CH_3OCHO (v = 0) and CH_3OCHO (v = 1) are (1.90±0.9)×10^-9 and (8.90±0.8)×10^-10, respectively. We also created the integrated emission maps of the detected molecules, and the observed molecules may have originated from the extended envelope of the protostar. We show that C_2H_5CN and HC_3N are most probably formed via the subsequential hydrogenation of the CH_2CHCN and the reaction between C_2H_2 and CN on the grain surface of IRAS 18089-1732. We found that NH_2CHO is probably produced due to the reaction between NH_2 and H_2CO in the gas phase. Similarly, CH_3OCHO is possibly created via the reaction between radical CH_3O and radical HCO on the grain surface of IRAS 18089-1732.