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Raman spectrum of thymidine-13C5, in which five C atoms of the deoxyribose moiety are uniformly substituted with 13C atoms, has been examined in the crystalline state with 488.0 nm excitation. Some of the Raman bands were observed at appreciably shifted frequencies from those of the corresponding Raman bands of the natural thymidine, and they were assigned to some vibrations involving deoxyribose motions.

Two isomers of inosine-5′-thiophosphates, inosine-5′-phosphorothionate and 5′-deoxy-5′-thioinosine-5′-phosphorothioate, were synthesized by the direct phosphorylation of inosine with phosphorus thiochloride, and by the treatment of 5′-deoxy-5′-iodoinosine with trisodium phosphorothioate, respectively. The structure of the thiophosphate residues was identified by means of 31P NMR. The flavoring activities of these thiophosphates were measured as the synergistic strength with monosodium glutamate; it was found that the strength of each compound was lower than that of inosine-5′-phosphate.

The NMR spectra of [2.2]metacyclophane have been shown to be held unchanged over a wide range of temperature, ca. −80 to 190°C, indicating that the ten-membered ring system undergoes no inversion and is frozen in a chair conformation. It may, then, be expected that suitably substituted derivatives of [2.2]metacyclophane would become disymmetric due to restricted inversion; such was proved to be the case by carrying out the optical resolution of the 4, 14-di-substituted derivatives. The 4,14-dimethyl derivative was resolved by means of a complex formation with Newman’s reagent, [α]57826=−3.4 and +4.2°. 4,14-Dicarboxylic acid was also resolved by converting it to the quinine salt, [α]D22=+5.0°.

Dimethyl sulfoxide (DMSO), under acidic conditions, is known to yield formaldehyde as one of its decomposition products. A new method of synthesizing dialkoxymethanes, which consists of the treatment of alcohols with a DMSO-PPA (polyphosphoric acid) mixture, has been shown to be convenient and also generally applicable. Under mild conditions, five primary alcohols and four secondary alcohols are converted to the corresponding formals in 50—80 and 30—40% yields respectively. Dimethyl disulfide, bis(methylthio) methane and methylthiomethyl ether and an oxidation product of the alcohol have been shown to be the main by-products in this reaction. The examination of the NMR spectra has revealed that the acetal methylene protons of dialkoxymethanes made from (±)-secondary alcohols are observed as an AB quartet and as a singlet, each arising from meso and racemic compounds, respectively.

The crystal structure of 5,5-dimethyl-2-oxo-2-hydroxy-l,3,2-dioxaphosphorinane monohydrate (I) has been determined by the three dimensional X-ray diffraction method. The crystals belong to monoclinic system, with space group P21. The unit cell dimensions are; a=9.50, b=5.86, c=8.31 A, β=106°8′, and two molecules per unit cell. The six-membered dioxaphosphorinane ring has a chair conformation, with P=O bond in equatorial position. The bond angles and distances of the phosphate group are similar to those found in the corresponding acyclic phosphates.