Table 3.

Monomer coupling, and cross-coupling patterns extracted from literature. M1, M2 represent the individual monomer unit and O1 and O2 represent two or more units connected forming a lignin chain (L).

Linear									Branched
Dimer structures					Oligomer and monomer				Oligomer cross-coupling
M1	M2	β-O-4	β-β	β-5	O1	M1	β-O-4	β-5	O1	O2	4-O-5	5-5
G	G	✓	✓	✓	L-G	G	✓	✓	L-G	L-G	✓	✓
S	S	✓	✓	✗	L-S	S	✓	✗	L-S	L-S	✗	✗
S	G	✓	✓	✓	L-S	G	✓	✓	L-G	L-S	✗	✗
G	S	✓	✓	✗	L-G	S	✓	✗	L-S	L-G	✓	✗