Abstract: A process for preparing pharmaceutically active compounds of formula (I) or a salt thereof wherein R1, n, m, R3, R6, X1, X2, X3 and X4 are as defined in the specification, is described. Novel intermediates are also described and claimed.

Abstract: A process for preparing pharmaceutically active compounds of formula (I) or a salt thereof wherein R1, n, m, R3, R6, X1, X2, X3 and X4 are as defined in the specification, is described. Novel intermediates are also described and claimed.

Abstract: A method for the synthesis of an ?,?-unsaturated ketone useful for making substituted 1,4-dihydropyridines is described by reacting an aldehyde with pyrrolidine and then adding a ketone followed by trifluoroacetic acid at low temperature. The synthesis is used in a process for making substituted 1,4-dihydropyridines wherein a vinylogous amide is prepared by reacting a 1,3-cyclohexanedione with a phenylethylamine. The ?,?-unsaturated ketone can be reacted with a vinylogous amide to form a 1,5-diketone which can be converted to a substituted 1,4-dihydropyridine.

Abstract: A method for the synthesis of an &agr;,&bgr;-unsaturated ketone useful for making substituted 1,4-dihydropyridines is described by reacting an aldehyde with pyrrolidine and then adding a ketone followed by trifluoroacetic acid at low temperature. The synthesis is used in a process for making substituted 1,4-dihydropyridines wherein a vinylogous amide is prepared by reacting a 1,3-cyclohexanedione with a phenylethylamine. The &agr;,&bgr;-unsaturated ketone can be reacted with a vinylogous amide to form a 1,5-diketone which can be converted to a substituted 1,4-dihydropyridine.

Abstract: A portable headlamp that is particularly designed for use with bicycles integrates a number of essential features and functions desired by modem bicyclists. The headlamp has an easily removable and universally mountable fastening system that requires no tools to install. The mounting system includes a rotary joint that enables a headlamp to be pointed in any desired direction while maintaining a constant friction that can be set by the user. A focussable light beam enables the operator to vary the light distribution pattern, thereby making the headlamp suitable for use under a number of different conditions. The electrical system for the headlamp can be readily upgraded to accommodate the needs of different riding conditions, without requiring additional parts.

Abstract: A portable headlamp that is particularly designed for use with bicycles integrates a number of essential features and functions desired by modern bicyclists. The headlamp has an easily removable and universally mountable fastening system that requires no tools to install. The mounting system includes a rotary joint that enables a headlamp to be pointed in any desired direction while maintaining a constant friction that can be set by the user. A focussable light beam enables the operator to vary the light distribution pattern, thereby making the headlamp suitable for use under a number of different conditions. The electrical system for the headlamp can be readily upgraded to accommodate the needs of different riding conditions, without requiring additional parts.