Abstract: Dioxane is produced by reaction of ethylene glycol or a polyethylene glycol using an acid catalyst. The reaction product containing dioxane, water and byproducts is subjected to extractive distillation with a high-boiling agent which is miscible with water.

Abstract: High molecular weight aromatic copolyamides which contain a small proportion of structural units having 2,3-(1H,3H)-quinazoline dione rings are disclosed. The presence of quinazolinedione ring units in the copolyamide results in an increased moisture absorption capacity. By using small amounts of quinazoline dione units, the good physical properties of the corresponding quinazoline dione-free polyamide are substantially retained while the moisture absorption is significantly increased. Larger amounts of quinazoline dione units than contemplated (15 mol percent and more) do not improve the moisture absorption further and adversely affect the physical properties. The copolyamides are useful in textile applications in which the improved moisture absorption serves to make clothing prepared from such textiles more comfortable.

Abstract: 2-Phenyl-4(3H)-quinazolones bearing a urethane or thiourethane group on the 2-phenyl substituent, a second urethane or thiourethane group on the benzo ring of the quinazolone nucleus and an alkyl, cycloalkyl or phenyl group in the 3-position are prepared by treating the corresponding bis-amino compound with an acid derivative or the corresponding bis(isocyanate) or bis(isothiocyanate) with an alcohol. The compounds, of which 2-[3'-(methoxycarbonylamino)-phenyl]-3-phenyl-6-methoxycarbonylamino-4-(3H )-quinazolone is a typical embodiment, are cytostatic agents.