Appendix 1—table 9. List of all modular metabolites referred to in the text and Figures.

Compound number	SMID ID	IUPAC Name	Evidence	Structure
1	icas#3	(R)−8-(((2R,3R,5R,6S)−5-((1H-indole-3-carbonyl)oxy)−3-hydroxy-6-methyltetrahydro-2H-pyran-2-yl)oxy)nonanoic acid	Previously identified via synthesis (Srinivasan et al., 2012)
2	ascr#8	4-((R,E)−6-(((2R,3R,5R,6S)−3,5-dihydroxy-6-methyltetrahydro-2H-pyran-2-yl)oxy)hept-2-enamido)benzoic acid	Previously identified via synthesis (Pungaliya et al., 2009)
3	uglas#11	(2R,3R,4S,5R,6R)−5-hydroxy-6-(hydroxymethyl)−4-(phosphonooxy)−2-(2,6,8-trioxo-1,2,6,7,8,9-hexahydro-3H-purin-3-yl)tetrahydro-2H-pyran-3-yl (R)−6-(((2R,3R,5R,6S)−3,5-dihydroxy-6-methyltetrahydro-2H-pyran-2-yl)oxy)heptanoate	Previously identified via synthesis (Curtis et al., 2020)
4	ubas#3	(R)−4-(((2R,3R,5R,6S)−3-hydroxy-6-methyl-5-(((R)−2-methyl-3-ureidopropanoyl)oxy)tetrahydro-2H-pyran-2-yl)oxy)pentanoic acid	Previously inferred via tandem mass spectrometry (Falcke et al., 2018)
5	ascr#1	(R)−6-(((2R,3R,5R,6S)−3,5-dihydroxy-6-methyltetrahydro-2H-pyran-2-yl)oxy)heptanoic acid	Previously identified via NMR and synthesis (Jeong et al., 2005)
6	gluric#1	3-((2R,3R,4S,5S,6R)−3,4,5-trihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2-yl)−7,9-dihydro-1H-purine-2,6,8 (3H)-trione	Previously identified via synthesis (Curtis et al., 2020)
7	ascr#7	(R,E)−6-(((2R,3R,5R,6S)−3,5-dihydroxy-6-methyltetrahydro-2H-pyran-2-yl)oxy)hept-2-enoic acid	Previously identified via synthesis (Pungaliya et al., 2009)
8	PABA	4-Aminobenzoic acid	Commercial product (Sigma-Aldrich)
9	ascr#3	(R,E)−8-(((2R,3R,5R,6S)−3,5-dihydroxy-6-methyltetrahydro-2H-pyran-2-yl)oxy)non-2-enoic acid	Previously identified via synthesis (Butcher et al., 2007)
10	ascr#10	(R)−8-(((2R,3R,5R,6S)−3,5-dihydroxy-6-methyltetrahydro-2H-pyran-2-yl)oxy)nonanoic acid	Previously identified via synthesis (Srinivasan et al., 2012)
11		1H-indole-3-carboxylic acid	Commercial product (Sigma-Aldrich)
12		(R)−4-((2-hydroxy-2-(4-hydroxyphenyl)ethyl)amino)−4-oxobutanoic acid	Identified via synthesis (This manuscript)
13	iglas#1	((2R,3S,4S,5R,6R)−3,4,5-trihydroxy-6-(1H-indol-1-yl)tetrahydro-2H-pyran-2-yl)methyl (R)−6-(((2R,3R,5R,6S)−3,5-dihydroxy-6-methyltetrahydro-2H-pyran-2-yl)oxy)heptanoate	Previously identified via synthesis (Artyukhin et al., 2018)
14	glas#10	(2S,3R,4S,5S,6R)−3,4,5-trihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2-yl (R)−8-(((2R,3R,5R,6S)−3,5-dihydroxy-6-methyltetrahydro-2H-pyran-2-yl)oxy)nonanoate	Previously identified via NMR and synthesis (Coburn et al., 2013)
15	iglu#1	(2R,3S,4S,5R,6R)−2-(hydroxymethyl)−6-(1H-indol-1-yl)tetrahydro-2H-pyran-3,4,5-triol	Previously identified via NMR and synthesis (Coburn et al., 2013)
16	iglu#2	(2R,3R,4S,5R,6R)−3,5-dihydroxy-2-(hydroxymethyl)−6-(1H-indol-1-yl)tetrahydro-2H-pyran-4-yl dihydrogen phosphate	Previously identified via NMR (Coburn et al., 2013)
17	angl#1	(2S,3R,4S,5S,6R)−3,4,5-trihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2-yl 2-aminobenzoate	Previously identified via NMR and synthesis (Coburn et al., 2013)
18	angl#2	(2S,3R,4S,5R,6R)−3,5-dihydroxy-6-(hydroxymethyl)−4-(phosphonooxy)tetrahydro-2H-pyran-2-yl 2-aminobenzoate	Previously identified via NMR (Coburn et al., 2013)
19	iglu#4	(2R,3R,4S,5R,6R)−3,5-dihydroxy-6-(1H-indol-1-yl)−4-(phosphonooxy)tetrahydro-2H-(pyran-2-yl)methyl 2-aminobenzoate	Proposed structure, based on identification of non-phosphorylated derivative (34) via synthesis (This manuscript)
20	iglu#6	((2R,3R,4S,5R,6R)−3,5-dihydroxy-6-(1H-indol-1-yl)−4-(phosphonooxy)tetrahydro-2H-pyran-2-yl)methyl nicotinate	Proposed structure, based on identification of non-phosphorylated derivative (SI-2) via synthesis (This manuscript)
21	iglu#8	((2R,3R,4S,5R,6R)−3,5-dihydroxy-6-(1H-indol-1-yl)−4-(phosphonooxy)tetrahydro-2H-pyran-2-yl)methyl (E)−2-methylbut-2-enoate	Proposed structure, based on identification of non-phosphorylated derivative (SI-3) via synthesis (This manuscript)
22	iglu#10	((2R,3R,4S,5R,6R)−3,5-dihydroxy-6-(1H-indol-1-yl)−4-(phosphonooxy)tetrahydro-2H-pyran-2-yl)methyl 1H-pyrrole-2-carboxylate	Proposed structure, based on identification of non-phosphorylated derivative (SI-4) via synthesis (This manuscript)
23	iglu#12	((2R,3R,4S,5R,6R)−3,5-dihydroxy-6-(1H-indol-1-yl)−4-(phosphonooxy)tetrahydro-2H-pyran-2-yl)methyl benzoate	Proposed structure. Inferred via tandem mass spectrometry (This manuscript)
24	iglu#41	(2R,3R,4S,5R,6R)−6-(((2-aminobenzoyl)oxy)methyl)−5-hydroxy-2-(1H-indol-1-yl)−4-(phosphonooxy)tetrahydro-2H-pyran-3-yl 1H-pyrrole-2-carboxylate	Proposed structure. Inferred from iglu#3 (34) via tandem mass spectrometry (This manuscript)
25	angl#4	((2R,3R,4S,5R,6S)−6-((2-aminobenzoyl)oxy)−3,5-dihydroxy-4-(phosphonooxy)tetrahydro-2H-pyran-2-yl)methyl 2-aminobenzoate	Proposed structure. Inferred from angl#3 (SI 5) via tandem mass spectrometry (This manuscript)
26	tyglu#4	((2R,3R,4S,5R,6R)−5-((2-aminobenzoyl)oxy)−3-hydroxy-6-((4-(2-aminoethyl)phenoxy)−4-(phosphonooxy)tetrahydro-2H-pyran-2-yl))methyl 2-aminobenzoate	Proposed structure. Initially described (O'Donnell et al., 2020) and further inferred via tandem mass spectrometry (This manuscript)
27	ascr#81	(4-((R,E)−6-(((2R,3R,5R,6S)−3,5-dihydroxy-6-methyltetrahydro-2H-pyran-2-yl)oxy)hept-2-enamido)benzoyl)-L-glutamic acid	Identified via synthesis (Artyukhin et al., 2018)
28	ascr#82	((S)−4-carboxy-4-(4-((R,E)−6-(((2R,3R,5R,6S)−3,5-dihydroxy-6-methyltetrahydro-2H-pyran-2-yl)oxy)hept-2-enamido)benzamido)butanoyl)-L-glutamic acid	Previously inferred via tandem mass spectrometry (Artyukhin et al., 2018)
29	PABA-glu	(4-aminobenzoyl)-L-glutamic acid	Identified via synthesis (This manuscript)
30	uglas#1	(2R,3R,4S,5S,6R)−4,5-dihydroxy-6-(hydroxymethyl)−2-(2,6,8-trioxo-1,2,6,7,8,9-hexahydro-3H-purin-3-yl)tetrahydro-2H-pyran-3-yl (R)−6-(((2R,3R,5R,6S)−3,5-dihydroxy-6-methyltetrahydro-2H-pyran-2-yl)oxy)heptanoate	Identified via synthesis (Curtis et al., 2020)
31	uglas#14	((2R,3S,4S,5R,6R)−3,4,5-trihydroxy-6-(2,6,8-trioxo-1,2,6,7,8,9-hexahydro-3H-purin-3-yl)tetrahydro-2H-pyran-2-yl)methyl (R)−6-(((2R,3R,5R,6S)−3,5-dihydroxy-6-methyltetrahydro-2H-pyran-2-yl)oxy)heptanoate	Identified via synthesis (Curtis et al., 2020)
32	uglas#15	((2R,3R,4S,5R,6R)−3,5-dihydroxy-4-(phosphonooxy)−6-(2,6,8-trioxo-1,2,6,7,8,9-hexahydro-3H-purin-3-yl)tetrahydro-2H-pyran-2-yl)methyl (R)−6-(((2R,3R,5R,6S)−3,5-dihydroxy-6-methyltetrahydro-2H-pyran-2-yl)oxy)heptanoate	Previously inferred via tandem mass spectrometry (Artyukhin et al., 2018; Curtis et al., 2020)
33		2-Aminobenzoic acid	Commercial product (Sigma-Aldrich)
34	iglu#3	((2R,3S,4S,5R,6R)−3,4,5-trihydroxy-6-(1H-indol-1-yl)tetrahydro-2H-pyran-2-yl)methyl 2-aminobenzoate	Identified via synthesis (This manuscript)
35	icas#2	(2S,3R,5R,6R)−5-hydroxy-2-methyl-6-(((R)−5-oxohexan-2-yl)oxy)tetrahydro-2H-pyran-3-yl 1H-indole-3-carboxylate	Identified via synthesis (Dong et al., 2016)
36	icas#6.2	(2S,3R,5R,6R)−5-hydroxy-6-(((2R,5S)−5-hydroxyhexan-2-yl)oxy)−2-methyltetrahydro-2H-pyran-3-yl 1H-indole-3-carboxylate	Identified via synthesis (Dong et al., 2016)
SI 1		2-((tert-butoxycarbonyl)-amino)benzoic acid	Characterized via synthesis (This manuscript)
SI 2	iglu#5	((2R,3S,4S,5R,6R)−3,4,5-trihydroxy-6-(1H-indol-1-yl)tetrahydro-2H-pyran-2-yl)methyl nicotinate	Identified via synthesis (This manuscript)
SI 3	iglu#7	((2R,3S,4S,5R,6R)−3,4,5-trihydroxy-6-(1H-indol-1-yl)tetrahydro-2H-pyran-2-yl)methyl (E)−2-methylbut-2-enoate	Identified via synthesis (This manuscript)
SI 4	iglu#9	((2R,3S,4S,5R,6R)−3,4,5-trihydroxy-6-(1H-indol-1-yl)tetrahydro-2H-pyran-2-yl)methyl 1H-pyrrole-2-carboxylate	Identified via synthesis (This manuscript)
SI 5	angl#3	((2R,3S,4S,5R,6S)−6-((2-aminobenzoyl)oxy)−3,4,5-trihydroxytetrahydro-2H-pyran-2-yl)methyl 2-aminobenzoate	Proposed structure based on synthesis of a reference sample for MS (This manuscript)
SI 6	tyglu#6	(2R,3R,4S,5S,6R)−6-(((2-aminobenzoyl)oxy)methyl)−2-((4-(2-aminoethyl)-phenoxy))−5-hydroxy-4-(phosphonooxy)-tetrahydro-2H-pyran-3-yl nicotinate	Proposed structure. Initially described (O'Donnell et al., 2020) and further inferred via tandem mass spectrometry (This manuscript)