BIOC 302 Lecture Notes - Lecture 18: Adenosine, Deoxyribose, Nucleoside
Document Summary
Numbering of the nucleic acids have prime to difereniate between the purine or pyrimidine ring and the carbohydrate ring. The 1" carbon is the anomeric carbon - Glycosidic bond forms between the pentose and the base. Condensaion reacion to form the glycosidic bond - The nitrogenous base is aromaic and therefore is planar. The ketone on the nitrogenous base has resonance and can become an enol with a oh group - this process is called tautomerizaion. The sugar in deoxyribonucleosides is a derivaive of this: 2- deoxy-d-ribose. Dna: 2"-deoxy-d-ribose means that it is fully reduced. There is no hydroxyl group on the 2". The ring can exist in one of 4 main conformaions, referred to as sugar pucker . Aldehyde + alcohol hemi-acetal endo = rna. Pyrimidines: 6-membered ring, thymine -dna (uracil - rna) & cytosine. Aromaic structures: all sp2 hybridized atoms (6p, 6pi, planar. N has a lone pair in both pyridines and purines.
