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The infrared spectra of a number of N-substituted glycosylarnines have been examined over the ranges 1800-1 500 and 960-700 cm.-l; the spectra indicate the presence of a pyranose ring. Comparison of the spectra of the two isomeric N-phenyl-D-ribosylamines with those of methyl P-D-ribopyranoside and methyl and benzyl p-D-ribofuranoside, suggests that the ribosylamines are pyranose but a furanose structure cannot be entirely excluded here because of the large number of peaks present in the spectra. There is no spectroscopic evidence for an earlier suggestion that some of the glycosylamines have an acyclic structure. A number of new glycosylamines are described.

Antiallergic properties in the chromone series appear2"4 to be largely confined to those compounds which contain a carboxyl group at C-2. Replacement of a carboxyl by a 5tetrazolyl group in a biologically active carboxylic acid5"8 has sometimes resulted in retention of activity but rarely in an improvement in potency. This paper reports the synthesis and antiallergic properties of a number of chromones,9 such as Id and its substituted derivatives, which carry a 5-tetrazolyl group at C-2. The variations in structure are shown in Table I.

Various 1H,6H‐pyrano[2,3‐c]pyrazol‐6‐ones (III‐XXIII) were obtained from β‐keto esters and 1H‐pyrazol‐5‐ones or hydrazines. Nitrations, chlorinations and brominations of these pyranopyrazoles were also carried out giving the corresponding derivatives (XXIV‐LXIV). The pyrone ring is the more reactive one in these reactions and the preferred position of attack is the 5‐position. The substitution products are formed by the addition‐elimination route.