Top: molecular abundances with respect to H₂ for the following hot corinos: IRAS 4A2 (black; this work), I16293B (red), IRAS 2A (green), and B335 (blue). All the values are derived from interferometric observations. References: I16293B: Bisschop et al. (2008), Jørgensen et al. (2012); IRAS 2A: Persson et al. (2012), Taquet et al. (2015); B335: Imai et al. (2016). Bottom: molecular abundances with respect to H₂ derived in this work for IRAS 4A2 and IRAS 4A1 (upper limits). Blue symbols depict the values recently reported for the prestellar core L1544 by Vastel et al. (2014), López-Sepulcre et al. (2015), and Jiménez-Serra et al. (2016).