photogenerated acid are continued using different combinations of masks until all desired sequences in the array are completed final deprotection of the exocyclic amines and phosphates is carried by treatment with 0 5 m dbu in dry pyridine for 30 60 minutes at room temperature to remove the npeoc and cyanoethyl groups without cleavage of the linker the particular embodiments disclosed above are illustrative only as the invention may be modified and practiced in different but equivalent manners apparent to those skilled in the art having the benefit of the teachings herein more specifically it will be apparent that certain compounds that are chemically structurally and or functionally related to those disclosed herein may be substituted in the methods of this invention while the same or similar results would be achieved furthermore no limitations are intended to the details of construction or design herein shown other than as described in the claims below it is therefore evident that the particular embodiments disclosed above may be altered or modified and all such variations are considered within the scope and spirit of the invention accordingly the protection sought herein is as set forth in the claims below bunin b a et al j am chem soc 114 10997 10998 1992 bunin b a.