Trans-enoyl reductase; part of the gene cluster that mediates the biosynthesis of equisetin, a trans-fused decalin-containing tetramic acid with antimicrobial activity (PubMed:23614392). The PKS module of eqxS together with the enoylreductase eqxC catalyze the formation of the polyketide unit which is then conjugated to L-serine by the condensation domain of the eqxS NRPS module (PubMed:23614392). Activity of the Dieckmann cyclase domain (RED) results in release of the Dieckmann product intermediate (PubMed:23614392, PubMed:18652469). Diels-Alderase eqx3 is involved in endo-selective Diels-Alder cycloaddition to form the decalin ring, leading to the production of N-desmethylequisetin also called trichosetin (By similarity). Subsequent N-methylation is carried out by eqxD to give equisetin (PubMed:23614392). acetyl-CoA + ATP + 11 H(+) + L-serine + 7 malonyl-CoA + 8 NADPH + 2 S-adenosyl-L-methionine = (5S)-3-[(2E,6R,8E,10E,12E)-2,6-dimethyltetradeca-2,8,10,12-tetraenoyl]-5-(hydroxymethyl)pyrrolidine-2,4-dione + AMP + 7 CO2 + 8 CoA + diphosphate + 6 H2O + 8 NADP(+) + 2 S-adenosyl-L-homocysteine Mycotoxin biosynthesis. Monomer. Abolishes the production of equisetin and accumulates the intermediate trichosetin (PubMed:23614392). Belongs to the zinc-containing alcohol dehydrogenase family.