The present invention provides, for example, a compound mentioned below as a medicament for treating or preventing the diseases induced by production, secretion or deposition of amyloid- proteins. A compound of the formula (I): ##STR00001##
wherein R.sup.1, R.sup.2a, R.sup.2b, R.sup.3, R.sup.4a, R.sup.4b, ring A and the dashed lines are defined in the specification,
its pharmaceutically acceptable salt or a solvate thereof.

The present invention provides, for example, a compound mentioned below as a medicament for treating or preventing the diseases induced by production, secretion or deposition of amyloid- proteins. A compound of the formula (I): ##STR00001##
wherein R.sup.1, R.sup.2a, R.sup.2b, R.sup.3, R.sup.4a, R.sup.4b, ring A and the dashed lines are defined in the specification,
its pharmaceutically acceptable salt or a solvate thereof.

The present invention relates to a copolymer having several azide functionalities that can be prepared by cationic ring opening polymerisation. The copolymer comprises a first monomer unit and a second monomer unit which are different from each other.

The invention provides for methods for the synthesis of various compounds through reaction of carboxamide, or carboxamide derivatives, with various substituted or unsubstituted haloalkanols in a one-step, single vessel, reaction mechanism. Preferably, but not exclusively, the reaction proceeds in the absence of any solvents, catalyst, base, or any further reagents.

The invention provides for methods for the synthesis of various compounds through reaction of carboxamide, or carboxamide derivatives, with various substituted or unsubstituted haloalkanols in a one-step, single vessel, reaction mechanism. Preferably, but not exclusively, the reaction proceeds in the absence of any solvents, catalyst, base, or any further reagents.