The present invention relates to systems, compositions, and methods for the synthesis and use of imaging agents, or precursors thereof. An imaging agent precursor may be converted to an imaging agent using the methods described herein. In some cases, the imaging agent is enriched in .sup.18F. In some cases, an imaging agent may be used to image an area of interest in a subject, including, but not limited to, the heart, cardiovascular system, cardiac vessels, brain, and other organs. In some embodiments, methods and compositions for assessing perfusion and innervation mismatch in a portion of a subject are provided.

The present invention relates to systems, compositions, and methods for the synthesis and use of imaging agents, or precursors thereof. An imaging agent precursor may be converted to an imaging agent using the methods described herein. In some cases, the imaging agent is enriched in .sup.18F. In some cases, an imaging agent may be used to image an area of interest in a subject, including, but not limited to, the heart, cardiovascular system, cardiac vessels, brain, and other organs. In some embodiments, methods and compositions for assessing perfusion and innervation mismatch in a portion of a subject are provided.

Disclosed are a chiral multidentate ligand (I), a preparation, and an application thereof. In this method, compound (M1) is subjected to condensation with compound (M2) followed by amine deprotection in the presence of a deprotection reagent to obtain compound (M4). Compound (1) is subjected to deprotonation by butyl lithium and phosphorization followed by dimethylamino group substitution to produce compound (3). The compound (3) and the compound (M4) are reacted in the presence of triethylamine to produce chiral multidentate ligands.

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Disclosed are a chiral multidentate ligand (I), a preparation, and an application thereof. In this method, compound (M1) is subjected to condensation with compound (M2) followed by amine deprotection in the presence of a deprotection reagent to obtain compound (M4). Compound (1) is subjected to deprotonation by butyl lithium and phosphorization followed by dimethylamino group substitution to produce compound (3). The compound (3) and the compound (M4) are reacted in the presence of triethylamine to produce chiral multidentate ligands.

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Novel compounds that find use as imaging agents within nuclear medicine applications (PET imaging) for imaging of cardiac innervation are disclosed. These PET based radiotracers may exhibit increased stability, decreased NE release thereby reducing side effects, improved quantitative data, and/or high affinity for VMAT over prior radiotracers. In some instances the compounds are developed by derivatizing certain compounds with 18F in a variety of positions: aryl, alkyl, a keto, benzylic, beta-alkylethers, gamma-propylalkylethers and beta-proplylalkylethers. Alternatively or additionally, a methyl group a is added to the amine, and/or the catechol functionality is either eliminated or masked as a way of making these compounds more stable.

Novel compounds that find use as imaging agents within nuclear medicine applications (PET imaging) for imaging of cardiac innervation are disclosed. These PET based radiotracers may exhibit increased stability, decreased NE release thereby reducing side effects, improved quantitative data, and/or high affinity for VMAT over prior radiotracers. In some instances the compounds are developed by derivatizing certain compounds with 18F in a variety of positions: aryl, alkyl, a keto, benzylic, beta-alkylethers, gamma-propylalkylethers and beta-proplylalkylethers. Alternatively or additionally, a methyl group a is added to the amine, and/or the catechol functionality is either eliminated or masked as a way of making these compounds more stable.

The invention relates to process for the preparation of midodrine or pharmaceutically acceptable salts thereof. The invention also relates to process for the preparation of intermediates of midodrine.

The invention relates to process for the preparation of midodrine or pharmaceutically acceptable salts thereof. The invention also relates to process for the preparation of intermediates of midodrine.

Provided herein are compounds of Formula (I), or pharmaceutically acceptable salt thereof, wherein R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.6, and n are defined herein. Also provided herein are pharmaceutical compositions comprising a compound of Formula (I) or pharmaceutically acceptable salt thereof, and methods of using a compound of Formula (I) or pharmaceutically acceptable salt thereof, e.g., in the treatment of a mental health disease or disorder.

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Novel compounds that find use as imaging agents within nuclear medicine applications (PET imaging) for imaging of cardiac innervation are disclosed. These PET based radiotracers may exhibit increased stability, decreased NE release (thereby reducing side effects), improved quantitative data, and/or high affinity for VMAT over prior radiotracers. Methods of using the compounds to image cardiac innervation are also provided. In some instances the compounds are developed by derivatizing certain compounds with 18F in a variety of positions: aryl, alkyl, a keto, benzylic, beta-alkylethers, gamma-propylalkylethers and beta-proplylalkylethers. Alternatively or additionally, a methyl group a is added to the amine, and/or the catechol functionality is either eliminated or masked as a way of making these compounds more stable.