Guanidinations of primary amines were performed with 3,5-dimethylpyraz
olylformamidinium nitrate. 6-Deoxy-6-guanidino derivatives of unprotec
ted N-acetyl-glucosamine and of glucosamine were prepared, with both p
roducts existing as pyranoses. In the pentose series, 5-deoxy-5-guanid
inio-D-xylose nitrate (17) and -D-arabinose nitrate (22) were synthesi
zed. For both compounds, besides some alpha-D-xylo-pyranose and beta-D
-arabino-pyranose, mainly the furanoses are found.