Abstract: The invention relates to a quick coupling which is operable even under pressure, particularly for hydraulic lines, composed of two matable coupling halves in form of a plug and socket valve which can be arrested in the coupled position via a ball-locking arrangement, and which each have a valve body which is biased to closing position by closing springs and in the uncoupled condition of the coupling halves is held in closed condition, being guided in a star body which is mounted in a coupling body, of which one of the coupling halves has a fixed abutment which limits the stroke of the valve body in its open position, whereas the valve body of the other coupling half can perform a stroke equal to double the valve stroke of the other valve body and at the end of the single valve stroke a disengageable and engageable abutment is provided for releasing the double valve stroke respectively arresting this valve body in an open position corresponding to the single valve stroke.

Abstract: The present application discloses certain 2-substituted propoxy-3-cyano-5-hydroxypyridines. The compounds have pharmaceutical activity e.g. as antihypertensives.