4-Hydroxy-5-methoxydimethyltryptamine
4-Hydroxy-5-methoxydimethyltryptamine, also known as 4-HO-5-MeO-DMT or psilomethoxin, is a hypothetical novel psychedelic drug. It is the 4-hydroxy counterpart of 5-MeO-DMT, or the 5-methoxy counterpart of psilocin. It is structurally similar to other psychedelic  tryptamines, but very little is known about its effects. The only report of it in the chemical literature was a paper published by Marc Julia's group at the Pasteur Institute in 1965. This paper reports a 10 step synthesis of 4-HO-5-MeO-DMT from  ortho-vanillin. Alexander Shulgin hypothesized that 4-HO-5-MeO-DMT could be biosynthesized by feeding Psilocybe cultures with 5-MeO-DMT, referencing a 1988 study by Jochen Gartz where transformation of DET into 4-HO-DET and 4-PO-DET was reported using such a method, with neither compounds having ever been found in nature. References 

Entheogens
Tryptamines
Psychedelic drugs