in a comparative tolerance study with two different intravenous methylxanthine preparations , a theophylline-ethylendiamine preparation ( te-reference preparation ) was tested against a combination of theophylline , proxyphylline ( 7- ( 2-hydroxypropyl ) -theophylline ) and diprophylline ( 7- ( 2,3-dihydroxypropyl ) -theophylline ) ( neobiphyllin ; tpd = test preparation ) in 10 healthy volunteers by a single blind cross-over design .
C0013360
diprophylline
C0039771
theophylline