Oxazolo[5,4-d]pyrimidines can be considered as 9-oxa-purine analogs of naturally occurring nucleic acid bases. Interest in this ring system has increased due to recent reports of biologically active derivatives. In particular, 5-aminooxazolo[5,4-d]pyrimidine-7(6H)-ones (9-oxa-guanines) have been shown to inhibit ricin. The preparation of a series of 2-substituted 5-aminooxazolo[5,4-d]pyrimidin-...

The chemical changes occurring during embryonic development have been studied by several workers (l-3). In the hen’s egg there is very little nucleic acid present, whereas a considerable synthesis of both desoxypentose nucleic acid (DNA) and ribose nucleic acid (RNA) occurs in the embryo (4-6). Recently, methods for the determination of purines and pyrimidines in small amounts of tissue have be...

The metabolism of exogenous uridine, uridine 5’-monophosphate, and uracil by rat liver slices was studied using in vitro superfusion systems. Mixtures of 3Hand 14Clabeled uridine, uridine 5’-monophosphate, uracil, and erotic acid were superfused at a constant rate until an isotopic steady state was achieved. Isotopic ratios and concentrations of labeled pyrimidines were measured in tissue and p...

The reaction of nano-cellulose and antimony pentachloridein dichloromethane gave nano-cellulose-SbCl5. Also nano-cellulose-SbCl5 has beencharacterized by energy dispersive X-ray spectroscopy(EDX), scanning electron microscopy (SEM)and Fourier transform infrared spectroscopy(FTIR).Nano-cellulose-SbCl5has been applied as a nano-catalyst for synthesis of pyrano[2,3-d]pyrimidines from the simple on...

A common explanation of molecular recognition by the olfactory system posits that receptors recognize the structure or shape of the odorant molecule. We performed a rigorous test of shape recognition by replacing hydrogen with deuterium in odorants and asking whether Drosophila melanogaster can distinguish these identically shaped isotopes. We report that flies not only differentiate between is...

Poly((2edimethylamino)ethyl methacrylate) with 60,000 g/mol and a narrow polydispersity (1.12) was synthesized using group transfer polymerization in order to investigate the structure of poly ((2edimethylamino)ethyl methacrylate)/sodium dodecylsufate complexes in water. The synthesized polymer chain conformation in water was studied as a function of deuterated sodium dodecylsulfate concentrati...

Probing molecules using perdeuteration (i.e deuteration in which all hydrogen atoms are replaced by deuterium) is extremely useful in a wide range of biophysical techniques. In the case of lipids, the synthesis of the biologically relevant unsaturated perdeuterated lipids is challenging and not usually pursued. In this work, perdeuterated phospholipids and sterols from the yeast Pichia pastoris...