in length more preferably 1 20 carbons and even more preferably between 1 and 8 or 1 and 6 carbons it will be understood that the terms u201c substitution u201d and u201c substituted with u201d are art recognized and include the implicit proviso that such substitution is in accordance with permitted valence of the substituted atom and the substituent and that the substitution results in a stable compound e g which does not spontaneously undergo transformation such as by rearrangement cyclization elimination or other reaction the term u201c substituted u201d is also contemplated to include all permissible substituents of organic compounds in a broad aspect the permissible substituents include acyclic and cyclic branched and unbranched carbocyclic and heterocyclic aromatic and nonaromatic substituents of organic compounds illustrative substituents include for example those described herein above the permissible substituents may be one or more and the same or different for appropriate organic compounds for purposes of this invention the heteroatoms such as nitrogen may have hydrogen substituents and or any permissible substituents of organic compounds described herein which satisfy the valences of the heteroatoms this invention is not intended to be limited in any manner by the permissible substituents of organic compounds where r is hydrogen the protecting group can be any suitable hydroxyl.