Abstract: Compounds of formula I ##STR1## wherein R.sub.1 is OH or NH.sub.2 and R.sub.2 is H or NH.sub.2, R is H or lower alkyl, A is an alkyl chain optionally interrupted by heteroatoms and B is an amino acid, a di- or tri-peptide, are useful in human therapy.

Abstract: A device for fastening a catheter to an osteofibrous wall, for example, to a cranial theca (6) for draining cerebro spinal fluid or any other serous fluid therefrom, particularly for use in pediatric neurosurgery, comprising a tubular body (1) arranged to receive a catheter (10), at least one transverse end foot (2) for insertion into an aperture (7) in the cranial theca (6), and a locking element (4) which can be fitted in opposite relationship with the foot (2) so as to bear on the outer surface of the cranial theca (6) in close liquid-tight contact therewith.

Abstract: The invention relates to a series of purine derivatives of formula (I) ##STR1## wherein R is hydrogen or NH.sub.2, n is an integer from 1 to 6, R.sup.1 is one of the following chains: ##STR2## wherein R.sup.2 is the residue of an aminoacid, R.sup.3 is hydrogen or the residue of an oligopeptide and R.sup.4 is OH or the residue of an oligopeptide.