Abstract: The invention is the use of a PDE10A inhibitor to treat or prevent autism spectrum disorders. More particularly, a method of treating or preventing an autism spectrum disorder selected from the group consisting of autistic disorder, CDKL5 deficiency disorder, childhood disintegrative disorder, Rett syndrome, Fragile X syndrome, Kleefstra syndrome, Pitt Hopkins syndrome, Angelman syndrome, Kabuki syndrome, Asperger's syndrome, Heller's syndrome and Pervasive Developmental Disorder, comprising administering an effective amount of 1-[2-fluoro-4-(1H-pyrazol-1-yl)phenyl]-5-methoxy-3-(1-phenyl-1H-pyrazol-5-yl)pyridazin-4(1H)-one or a salt thereof to a mammal Additionally, a medicament for the treatment or prevention of autism spectrum disorders, and the use of a PDE10A inhibitor in the manufacture of a medicament for the treatment or prevention of autism spectrum disorders.

Abstract: The compounds of formula (1) in which R1, R4, A and X have the meanings as given in the description, are novel effective EP2 agonists.

Abstract: The compounds of formula (1) in which R1, R4, A and X have the meanings as given in the description, are novel effective EP2 agonists.

Abstract: The compounds of formula (I), wherein ring D and ring E together form a fused ring system selected from formula (II), (III), (IV), (V), (VI), (VII), and the salts of these compounds are novel, effective inhibitors of histone deacetylases.

Abstract: The compounds of formula (I), wherein ring D and ring E together form a fused ring system selected from formula (II), (III), (IV), (V), (VI), (VII), and the salts of these compounds are novel, effective inhibitors of histone deacetylases.