Detection and prebiotic chemistry of possible glycine precursor molecule methylenimine towards the hot molecular core G10.47+0.03

Amino acids are essential for the synthesis of protein. Amino acids contain both amine (R-NH₂) and carboxylic acid (R-COOH) functional groups, which help to understand the possible formation mechanism of life in the universe. Among the 20 types of amino acids, glycine (NH₂CH₂COOH) is known as the simplest non-essential amino acid. In the last 40 years, all surveys of NH₂CH₂COOH in the interstellar medium, especially in the star-formation regions, have failed at the millimeter and sub-millimeter wavelengths. We aimed to identify the possible precursors of NH₂CH₂COOH, because it is highly challenging to identify NH₂CH₂COOH in the interstellar medium. Many laboratory experiments have suggested that methylenimine (CH₂NH) plays a key role as a possible precursor of NH₂CH₂COOH in the star-formation regions via the Strecker synthesis reaction. After spectral analysis using the local thermodynamic equilibrium (LTE) model, we successfully identified the rotational emission lines of CH₂NH towards the hot molecular core G10. 47+0. 03 using the Atacama Compact Array (ACA). The estimated column density of CH₂NH towards G10. 47+0. 03 is (3. 400. 2) 10^15 cm^-2 with a rotational temperature of 218. 7020 K, which is estimated from the rotational diagram. The fractional abundance of CH₂NH with respect to H₂ towards G10. 47+0. 03 is 2. 6110^-8. We found that the derived abundance of CH₂NH agree fairly well with the existing two-phase warm-up chemical modelling abundance value of CH₂NH. We discuss the possible formation pathways of CH₂NH within the context of hot molecular cores, and we find that CH₂NH is likely mainly formed via neutral-neutral gas-phase reactions of CH₃ and NH radicals towards G10. 47+0. 03.