ABSTRACT
A series of 4-bicyclic heteroaryl 1,2,3,4-tetrahydroisoquinoline inhibitors of the serotonin transporter (SERT), norepinephrine transporter (NET), and dopamine transporter (DAT) was discovered. The synthesis and structure-activity relationship (SAR) of these triple reuptake inhibitors (TRIs) will be discussed. Compound 10i (AMR-2), a very potent inhibitor of SERT, NET, and DAT, showed efficacy in the rat forced-swim and mouse tail suspension models with minimum effective doses of 0.3 and 1 mg/kg (po), respectively. At efficacious doses in these assays, 10i exhibited substantial occupancy levels at the three transporters in both rat and mouse brain. The study of the metabolism of 10i revealed the formation of a significant active metabolite, compound 13.
ABSTRACT
Novel 4-phenyl tetrahydroisoquinolines that inhibit both dopamine and norepinephrine transporters were designed and prepared. In this Letter, we describe the synthesis, in vitro activity and associated structure-activity relationships of this series. We also report the ex vivo NET occupancy of a representative compound, 41.
Subject(s)
Dopamine Uptake Inhibitors/chemistry , Tetrahydroisoquinolines/chemistry , Dopamine Plasma Membrane Transport Proteins/antagonists & inhibitors , Dopamine Plasma Membrane Transport Proteins/metabolism , Dopamine Uptake Inhibitors/chemical synthesis , Dopamine Uptake Inhibitors/metabolism , Kinetics , Norepinephrine Plasma Membrane Transport Proteins/antagonists & inhibitors , Norepinephrine Plasma Membrane Transport Proteins/metabolism , Protein Binding , Serotonin Plasma Membrane Transport Proteins/chemistry , Serotonin Plasma Membrane Transport Proteins/metabolism , Selective Serotonin Reuptake Inhibitors/chemical synthesis , Selective Serotonin Reuptake Inhibitors/chemistry , Selective Serotonin Reuptake Inhibitors/metabolism , Structure-Activity Relationship , Tetrahydroisoquinolines/chemical synthesis , Tetrahydroisoquinolines/metabolismABSTRACT
The asymmetric synthesis of the antibacterial natural product, streptophenazine G, has been achieved by employing asymmetric alkylation and asymmetric aldol reactions using chiral oxazolidinones as the key steps. The originally proposed structure for streptophenazine G has been revised, and its absolute configuration has been determined to be 1'S,2'R,6'S. The asymmetric total synthesis of 6'-epi-streptophenazine G is also described.
Subject(s)
Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/chemical synthesis , Biological Products/chemistry , Biological Products/chemical synthesis , Phenazines/chemistry , Phenazines/chemical synthesis , Streptomyces/chemistry , Alkylation , Molecular Structure , StereoisomerismABSTRACT
A total synthesis of both diastereomers of the originally proposed structure for streptophenazine A (1) has been achieved. However, both synthetic compounds are different from the natural product. Re-examination of NMR data reported for streptophenazine A and a concise total synthesis of both diastereomers of 17 (17a and 17b) led to the structural revision of streptophenazine A to 17b. Asymmetric synthesis of (-)-streptophenazine A was also conducted, and its absolute configuration was determined to be 1'S,2'R.
Subject(s)
Phenazines/chemistry , Phenazines/chemical synthesis , Magnetic Resonance Spectroscopy , Molecular Structure , Stereoisomerism , Streptomyces/chemistryABSTRACT
The asymmetric total synthesis of (+)-crassalactone D (4), a naturally occurring antitumor agent, has been achieved by employing an oxidative spirocyclization of furan 11 as the key step. Two close analogues, 7-epi-crassalactone D (14) and 5-epi-7-epi-crassalactone D (15), also have been prepared in the course of the synthesis of (+)-crassalactone D.
Subject(s)
Antineoplastic Agents, Phytogenic/chemical synthesis , Furans/chemical synthesis , Spiro Compounds/chemical synthesis , Antineoplastic Agents, Phytogenic/chemistry , Cyclization , Furans/chemistry , Spiro Compounds/chemistry , StereoisomerismABSTRACT
A series of trisubstituted cyclohexanes was designed, synthesized and evaluated as CC chemokine receptor 2 (CCR2) antagonists. This led to the identification of two distinct substitution patterns about the cyclohexane ring as potent and selective CCR2 antagonists. Compound 36 exhibited excellent binding (CCR2 IC(50)=2.4 nM) and functional antagonism (calcium flux IC(50)=2.0 nM and chemotaxis IC(50)=5.1 nM).
Subject(s)
Chemistry, Pharmaceutical/methods , Receptors, CCR2/antagonists & inhibitors , Receptors, CCR2/chemistry , Binding Sites , Calcium/chemistry , Chemokine CCL2/chemistry , Chemotaxis , Cyclohexanes/chemistry , Drug Design , Humans , Inhibitory Concentration 50 , Models, Chemical , Molecular Structure , Protein Binding , Structure-Activity RelationshipABSTRACT
Amiloride (1), the prototypical epithelial sodium channel (ENaC) blocker, has been administered with limited success as aerosol therapy for improving pulmonary function in patients with the genetic disorder cystic fibrosis. This study was conducted to synthesize and identify more potent, less reversible ENaC blockers, targeted for aerosol therapy and possessing minimal systemic renal activity. A series of novel 2-substituted acylguanidine analogues of amiloride were synthesized and evaluated for potency and reversibility on bronchial ENaC. All compounds tested were more potent and less reversible at blocking sodium-dependent short-circuit current than amiloride. Compounds 30-34 showed the greatest potency on ENaC with IC(50) values below 10 nM. A regioselective difference in potency was found (compounds 30, 39, and 40), whereas no stereospecific (compounds 33, 34) difference in potency on ENaC was displayed. Lead compound 32 was 102-fold more potent and 5-fold less reversible than amiloride and displayed the lowest IC(50) value ever reported for an ENaC blocker.
