obsolete 1-18:2-2-18:1-phosphatidylcholine desaturase activity (obsolete GO:0102854)
OBSOLETE. Catalysis of the reaction: 1-18:2-2-18:1-phosphatidylcholine + O2 + a reduced electron acceptor = 1-18:3-2-18:1-phosphatidylcholine + 2 H2O + an oxidized electron acceptor.