Synthesis of medronic acid monoesters and their purification by high-performance countercurrent chromatography or by hydroxyapatite

Synthesis and Theoretical Studies of Aromatic Azaborines

Organoboron compounds are well known for their use as synthetic building blocks in several significant reactions, e.g., palladium-catalyzed Suzuki-Miyaura cross-coupling. As an element, boron is fascinating; as part of a molecule it structurally resembles a three-valent atom, but if there is a lone pair of electrons nearby, the boron atom’s empty p-orbital may capture the lone pair and form a covalent bond. This is the main aspect that is challenging chemistry during the synthesis of boron containing molecules and may lead into unexpected reactions and products. To study this, we synthesized and studied novel aromatic azaborines for better understanding of their structures and reactions. Here, we report a one-pot method for the synthesis of substituted aromatic azaborines and computational studies of their structure to explain their observed chemical properties.

Semi-preparative high-performance countercurrent chromatography method for the purification of chemically synthesized ATP analogue, ApppI

An efficient high-performance countercurrent chromatography (HPCCC) based method has been developed for the purification of chemically synthesized 1-adenosin-5'-yl 3-(3-methylbut-3-enyl)triphosphoric acid diester (ApppI). ApppI is an adenosine triphosphate (ATP) analogue with biological significance due to its varied actions in the body. ApppI was synthesized and purified as its tetrabutylammonium (TBA) salt and converted successfully into its more practical sodium salt form after purification. The amount of TBA hydroxide (2.0, 2.5 and 3.0 eq) used in the synthesis of ApppI was shown to exert an effect on the purification process with HPCCC and on the overall yield (8%, 16% and 22%, respectively). 1-Adenosin-5'-yl 3-(3-methylbut-3-enyl)diphosphoric acid diester (AppI) was also isolated as a side product.