Overlap of contours corresponding to the velocity integrated species emission, ordered by their upper energy level, E_u. A spatial scale of 50 pc corresponds to ∼3″. The kinematic centre (α_ICRS = 00^h47^m33.14^s and δ_ICRS=−25°17′17.52″; Müller-Sánchez et al. 2010) is labelled by a filled black triangle. The black crosses mark the positions analysed in this work and correspond to GMC 7, GMC 6, pSSC 5 and pSSC 2. For reference, the position of GMC 3 and GMC 4 (Leroy et al. 2015) are indicated by magenta crosses in the panel a. The beam size if depicted in the lower left corner of each box. Contours of CH₃NH₂, CH₃CHO, CH₂NH, NH₂CHO, and C₂H₅OH are in grey, blue, orange, magenta, and green, respectively. a) Contour overlap of CH₃NH₂ (3_−1,1−2_0,0;E_u = 17 K) and CH₃CHO (1_1,5−1_0,5 (E+A); E_u = 19 K). Contours start at 3σ with steps of 3σ with 1σ = 42 and 25 mJy beam⁻¹ km s⁻¹, respectively. b) Contour overlap of CH₂NH (4_1,3−3_1,2;E_u = 39.8 K) with 1σ = 78 mJy beam⁻¹ km s⁻¹, CH₃CHO (9_2,9−8_1,8 (E+A); E_u = 43 K) with 1σ = 55 mJy beam⁻¹ km s⁻¹, NH₂CHO (8_0,8−7_0,7; E_u = 36 K) with 1σ = 58 mJy beam⁻¹ km s⁻¹, and t-C₂H₅OH (6₄−5₃; E_u = 37.7 K) with 1σ = 64 mJy beam⁻¹ km s⁻¹. Contours start at 3σ with steps of 3σ for CH₃CHO and t-C₂H₅OH, 8σ for CH₂NH, and 2σ for NH₂CHO. c) Contours overlap of CH₂NH (6_1,6−5_1,5;E_u = 69.6 K) with 1σ = 42 mJy beam⁻¹ km s⁻¹ and CH₃CHO (11_2,9−10_2,8 (E+A); E_u = 70.5 K) 1σ = 25 mJy beam⁻¹ km s⁻¹. Contours start at 3σ with steps of 5σ and 3σ for CH₂NH and CH₃CHO, respectively. d) Contour overlap of CH₂NH (8_1,7−8_0,8;E_u = 122.7 K), with 1σ = 61 mJy beam⁻¹ km s⁻¹ and NH₂CHO (15_2,14−14_2,13; E_u = 133.5 K) 1σ = 78 mJy beam⁻¹ km s⁻¹. Contours start at 3σ with steps of 2σ.