Reaction
2 S-adenosyl-L-methionine + C30 botryococcene = 2 S-adenosyl-L-homocysteine + 3,20-dimethyl-1,2,21,22-tetradehydro-2,3,20,21-tetrahydrobotryococcene (overall reaction); (1a) S-adenosyl-L-methionine + C30 botryococcene = S-adenosyl-L-homocysteine + 3-methyl-1,2-didehydro-2,3-dihydrobotryococcene; (1b) S-adenosyl-L-methionine + 3-methyl-1,2-didehydro-2,3-dihydrobotryococcene = S-adenosyl-L-homocysteine + 3,20-dimethyl-1,2,21,22-tetradehydro-2,3,20,21-tetrahydrobotryococcene; (2a) S-adenosyl-L-methionine + C30 botryococcene = S-adenosyl-L-homocysteine + 20-methyl-21,22-didehydro-20,21-dihydrobotryococcene; (2b) S-adenosyl-L-methionine + 20-methyl-21,22-didehydro-20,21-dihydrobotryococcene = S-adenosyl-L-homocysteine + 3,20-dimethyl-1,2,21,22-tetradehydro-2,3,20,21-tetrahydrobotryococcene