OligoCalc Chemical Modifications
When available, mousing over the modification name will give the chemical name
When available, clicking on the modification name will display the structure
Absorptivity is given at 260nm in Moles-1 cm-1
Please note that many of the chemical structures are for the phosphoramidite form of the compound before it is incorporated into the oligonucleotide, not the modification alone or after incorporation.
Most of the structures were courtesy of Glen Research at http://www.glenres.com/.