An efficient and versatile preparative approach is described, allowing for the preparation of DNA probes modified with an aldehyde group at the 3'- or 5'-end. The developed synthetic strategy allows for the preparation of a new family of phosphoramidites and solid supports compatible with the automated synthesis of modified oligonucleotide probes. These new reagents were prepared from intermediates 3 and 3a, obtained from the commercially available aleuritic acid 1. It was demonstrated that the new phosphoramidite reagents also could be used as new types of cleavable linkers. A new and efficient method for the production of 5' aldehyde-labeled DNA probes was developed.

We present a flexible and cost-efficient synthetic strategy for the preparation of a new family of phosphoramidite and solid-support reagents that can introduce a broad range of modifications into DNA probes. The key intermediate material 3 is synthesized using the inexpensive and commercially available 3-(tert-butyldimethylsiloxy)glutaric anhydride 1 and can be used as common starting material for the preparation of new labeling reagents.