I-hydrogen cyanide engenamanzi (i-prussic acid, HCN): uketshezi olusobala nepoyizini elibulalayo. Lapha yenziwa ngendlela kaWöhler kusuka ku-potassium ferrocyanide ne-sulphuric acid ehlanjululiwe, yomiswe phezu kwe-calcium chloride. Isetshenziselwa ukwenza i-acetone cyanohydrin, isinyathelo sokuqala siya engilazini ye-acrylic.