label: [(1->4)-alpha-D-galacturonosyl methyl ester](n) = [(1->4)-alpha-D-galacturonosyl methyl ester](n-1) + 4-deoxy-6-O-methyl-L-threo-hex-4-enopyranuronate
label_lc: [(1->4)-alpha-d-galacturonosyl methyl ester](n) = [(1->4)-alpha-d-galacturonosyl methyl ester](n-1) + 4-deoxy-6-o-methyl-l-threo-hex-4-enopyranuronate