(RS)-2-Oxo-4-(1-phenyl-ethyl-amino)-1,2-dihydro-quinoline-3-carb-oxy-lic acid.

The mol-ecular structure of the title compound, C(18)H(16)N(2)O(3), does not differ in the crystals of the racemic mixture, (I), and the pure enantiomer, (II). In their crystal structures, inversion dimers occur in (I) via N-H⋯O hydrogen bonds and infinite chains in (II) also via N-H⋯O hydrogen bonds.

Methyl 2-(4-hy-droxy-1-methyl-2-oxo-1,2-dihydro-quinolin-3-yl)acetate.

In the title compound, C(13)H(13)NO(4), the bicyclic quinolone fragment and the ester group are approximately orthogonal, making a dihedral angle of 83.3 (2)° and an intramolecular C-H⋯O interaction occurs. In the crystal, inter-molecular O-H⋯O hydrogen bonding generates a zigzag chain along the c axis.

[Drug pleurodesis, an alternative to surgical treatment of spontaneous pneumothorax].

The article describes the method of drug pleurodesis and determines the indications for its application. Study of the late-term results and the drawn conclusions provide evidence that the method of drug pleurodesis may de an alternative to operative treatment of spontaneous pneumothorax.