The Hebei Huarong company leads this molecule’s industrial production, which is done by fermenting Pseudomonas denitrificans. A synthesis of this molecule attached elements of the “A/D” approach from a camphor precursor to pentacyclenone. To synthesize this molecule, three amidine bridges were created through sulfide contractions done by a team (15[1])from Harvard and (15[1])ETH Zurich. (15[1])This molecule’s central ring is attached to a dimethylbenzimidazole (“di-methyl-benz-imid-azole”) ligand and an (*) adenosyl group that is replaced with a methyl by methionine synthase. This cofactor for methylmalonyl-CoA (10[1])mutase (10[1])contains a rare example of a biological carbon–metal bond. The total synthesis of this molecule inspired the development of the Woodward–Hoffmann (10[1])rules. (-5[2])Haptocorrin protects this molecule through the stomach so that it can be (10[1])absorbed by intrinsic factor. (10[1])For 10 points, name this vitamin (10[1])that is deficient in pernicious anemia and whose central (10[1])atom is cobalt. ■END■ (10[3])