Aspects of the present invention are directed to structurally modified opioids (SMOs) that result in improved modulating activity at the NMDAR and improved PK and PD parameters over existing drugs with NMDAR modulating activity. The structural modifications of an opioid or opioid enantiomer that result in the SMOs can be obtained by starting the synthetic process de novo; by modifying the synthetic process for the opioid at any intermediate step during the synthesis of the racemate or of one enantiomer; or by modifying the structure of the opioid or opioid enantiomer after the synthesis. The nitric acid ester substitutions are of particular relevance, especially when associated to deuterated substitutions and/or halogen substitutions.

Disclosed are compounds of Formulas (I), (II), (III), (IV), and (V): ##STR00001##
and/or a salt thereof, wherein R.sub.1 is —OH or —OP(O)(OH).sub.2, and X.sub.1, X.sub.2, X.sub.3, R.sub.2, R.sub.2a, R.sub.a, R.sub.b, and R.sub.c are defined herein. Also disclosed are methods of using such compounds as selective agonists for G protein-coupled receptor S1P.sub.1, and pharmaceutical compositions comprising such compounds. These compounds are useful in treating, preventing, or slowing the progression of diseases or disorders in a variety of therapeutic areas, such as autoimmune diseases and vascular disease.

Disclosed are compounds of Formulas (I), (II), (III), (IV), and (V): ##STR00001##
and/or a salt thereof, wherein R.sub.1 is —OH or —OP(O)(OH).sub.2, and X.sub.1, X.sub.2, X.sub.3, R.sub.2, R.sub.2a, R.sub.a, R.sub.b, and R.sub.c are defined herein. Also disclosed are methods of using such compounds as selective agonists for G protein-coupled receptor S1P.sub.1, and pharmaceutical compositions comprising such compounds. These compounds are useful in treating, preventing, or slowing the progression of diseases or disorders in a variety of therapeutic areas, such as autoimmune diseases and vascular disease.

Compounds of formula (I), wherein R.sub.1 is as defined in the claims, exhibit COMT enzyme inhibiting activity and are thus useful as COMT inhibitors. Methods of treatment and pharmaceutical dosage forms are also disclosed.

Compounds of formula (I), wherein R.sub.1 is as defined in the claims, exhibit COMT enzyme inhibiting activity and are thus useful as COMT inhibitors. Methods of treatment and pharmaceutical dosage forms are also disclosed.

Disclosed are compounds of Formulas (I), (II), (III), (IV), and (V):

##STR00001##

and/or a salt thereof, wherein R.sub.1 is OH or OP(O)(OH).sub.2, and X.sub.1, X.sub.2, X.sub.3, R.sub.2, R.sub.2a, R.sub.a, R.sub.b, and R.sub.c are defined herein. Also disclosed are methods of using such compounds as selective agonists for G protein-coupled receptor S1P.sub.1, and pharmaceutical compositions comprising such compounds. These compounds are useful in treating, preventing, or slowing the progression of diseases or disorders in a variety of therapeutic areas, such as autoimmune diseases and vascular disease.

Disclosed are compounds of Formulas (I), (II), (III), (IV), and (V):

##STR00001##

and/or a salt thereof, wherein R.sub.1 is OH or OP(O)(OH).sub.2, and X.sub.1, X.sub.2, X.sub.3, R.sub.2, R.sub.2a, R.sub.a, R.sub.b, and R.sub.c are defined herein. Also disclosed are methods of using such compounds as selective agonists for G protein-coupled receptor S1P.sub.1, and pharmaceutical compositions comprising such compounds. These compounds are useful in treating, preventing, or slowing the progression of diseases or disorders in a variety of therapeutic areas, such as autoimmune diseases and vascular disease.

Disclosed are compounds of Formulas (I), (II), (III), (IV), and (V): ##STR00001##
and/or a salt thereof, wherein R.sub.1 is OH or OP(O)(OH).sub.2, and X.sub.1, X.sub.2, X.sub.3, R.sub.2, R.sub.2a, R.sub.a, R.sub.b, and R.sub.c are defined herein. Also disclosed are methods of using such compounds as selective agonists for G protein-coupled receptor S1P.sub.1, and pharmaceutical compositions comprising such compounds. These compounds are useful in treating, preventing, or slowing the progression of diseases or disorders in a variety of therapeutic areas, such as autoimmune diseases and vascular disease.

Disclosed are compounds of Formulas (I), (II), (III), (IV), and (V): ##STR00001##
and/or a salt thereof, wherein R.sub.1 is OH or OP(O)(OH).sub.2, and X.sub.1, X.sub.2, X.sub.3, R.sub.2, R.sub.2a, R.sub.a, R.sub.b, and R.sub.c are defined herein. Also disclosed are methods of using such compounds as selective agonists for G protein-coupled receptor S1P.sub.1, and pharmaceutical compositions comprising such compounds. These compounds are useful in treating, preventing, or slowing the progression of diseases or disorders in a variety of therapeutic areas, such as autoimmune diseases and vascular disease.

The present invention relates to: a compound as a ligand in a variety of catalytic organic synthetic reactions; a method for producing the compound; a synthetic intermediate of the compound; and a transition metal complex which has the compound as a ligand. The compound includes a compound represented by the following general formula (1.sup.A): ##STR00001##