[yitzik]

After encountering a few compounds which their name includes the prefix "TETRA HYDRO '' I'm wondering what that prefix actually means? for example THC (Tetrahydrocannabinol) and also THF folic acid (tetra hydro folate) or THF (tetrahydrofuran) what that "tetra hydro" mean?? I couldn't recognize any detail in their structure that implies for this "TETRA HYDRO" character and how to determine in which position in the molecule thouse "hydro"'s should appear....
does hydro here means water? Hydrogen ? or maybe complex with four molecules of water?
sorry for the lack of knowledge, i couldn't find any information on the web about this type of nomenclature....

[Babcock_Hall]

The easiest way for you to answer your question is to compare the structures of furan and tetrahydrofuran, or to compare the structures of folate (Vitamin B3 IIRC) and tetrahydrofolate.  There is a simple method to calculate the oxidation number of a carbon atoms, which might be put to good use here.  You raise an interesting point about regiochemistry, but to the best of my knowledge, there is only one isomer of tetrahydrofolate that is commonly encountered biologically.

[yitzik]

thanks!