ABSTRACT
A novel and convenient one-pot sequential cascade method for the preparation of 2-trifluoromethylquinazolin-4(3 H)-ones is described. Trifluoroacetic acid (TFA) was employed as inexpensive and readily available CF3 source, which in the presence of T3P was condensed with a variety of anthranilic acids and amines to provide the products in up to 75% yield. The protocol was proved to be robust on 80 g scale, and the synthetic versatility of the prepared quinazolinon-4-ones was demonstrated by derivatization to further useful building blocks.
Subject(s)
Quinazolines/chemistry , Quinazolines/chemical synthesis , Trifluoroacetic Acid/chemistry , Catalysis , Chemistry Techniques, Synthetic , MethylationABSTRACT
Starting from suvorexant (trade name Belsomra), we successfully identified interesting templates leading to potent dual orexin receptor antagonists (DORAs) via a scaffold-hopping approach. Structure-activity relationship optimization allowed us not only to improve the antagonistic potency on both orexinâ 1 and orexinâ 2 receptors (Ox1 and Ox2, respectively), but also to increase metabolic stability in human liver microsomes (HLM), decrease time-dependent inhibition of cytochrome P450 (CYP) 3A4, and decrease P-glycoprotein (Pgp)-mediated efflux. Compound 80 c [{(1S,6R)-3-(6,7-difluoroquinoxalin-2-yl)-3,8-diazabicyclo[4.2.0]octan-8-yl}(4-methyl-[1,1'-biphenyl]-2-yl)methanone] is a potent and selective DORA that inhibits the stimulating effects of orexin peptides OXA and OXB at both Ox1 and Ox2. In calcium-release assays, 80 c was found to exhibit an insurmountable antagonistic profile at both Ox1 and Ox2, while displaying a sleep-promoting effect in rat and dog models, similar to that of the benchmark compound suvorexant.
Subject(s)
Cytochrome P-450 CYP3A Inhibitors/pharmacology , Drug Discovery , Orexin Receptor Antagonists/pharmacology , Orexin Receptors/metabolism , Animals , Cytochrome P-450 CYP3A/metabolism , Cytochrome P-450 CYP3A Inhibitors/chemical synthesis , Cytochrome P-450 CYP3A Inhibitors/chemistry , Dogs , Dose-Response Relationship, Drug , Humans , Male , Microsomes, Liver/chemistry , Microsomes, Liver/metabolism , Molecular Structure , Orexin Receptor Antagonists/chemical synthesis , Orexin Receptor Antagonists/chemistry , Rats , Rats, Wistar , Sleep/drug effects , Structure-Activity RelationshipABSTRACT
[reaction: see text] The thiolysis of alpha,beta-epoxycarboxylic acids 1a-e by thiols 2a,b is more efficient in water than in dichloromethane or SFC. At pH 9.0 phenylthiolate generally attacks the C-alpha carbon while at pH 4.0, and in the presence of InCl3 (10 mol %), the thiolysis is exclusively C-beta regioselective. In all cases, the processes are completely anti-diasteroselective, and the corresponding products 3, 4, and 5 have been isolated in good yields. Both water and catalysts have been recovered and reused.
ABSTRACT
Under solvent-free conditions, thiosalicylic acid (2) efficiently self-promotes the thiolysis of 1,2-epoxides 1, anti-stereoselectively and generally totally beta-regioselectively. The resulting beta-hydroxysulfide products 3 have been obtained in very good yields. Benzo[e]1,4-oxathiepin-5-ones 4 have been easily prepared in a regio- and diasteroselective manner and in satisfactory yields under SFC by a one-pot protocol including nucleophilic ring opening of 1,2-epoxides 1 by thiosalicylic acid (2) and thermally induced lactonization of beta-hydroxy arylsulfides 3. Solvent-free condition and the absence of any catalyst make this procedure atom-economical and environmentally friendly.
Subject(s)
Epoxy Compounds/chemistry , Esters/chemical synthesis , Heterocyclic Compounds, 3-Ring/chemical synthesis , Sulfhydryl Compounds/chemistry , Epoxy Compounds/chemical synthesis , Molecular Structure , Salicylates/chemistry , StereoisomerismABSTRACT
Beta-Amino alcohols N-2'-pyridylmethyl substituted 3 have been prepared in excellent yields under mild conditions by the first Lewis acid-catalyzed aminolysis of 1,2-epoxides 1 with the bihaptic amine 2-picolylamine (2) with use of 5 mol % of Al(OTf)(3) under solvent-free conditions. As a representative of a new class of ionic liquids, cis-5-[(4'-methylphenyl)sulfonyl]-1,2,3,4,4a,5,6,11a-octahydropyrido[1,2-a]quinoxalin-11-ium methanesulfonate (6) and its chloride derivative 7 have been synthesized under environmentally friendly conditions by the one-pot aminolysis of cyclohexene oxide (1a) with 2 and intramolecular cyclization of the resulting 2-[(pyridin-2'-yl)methylamino]cyclohexanol (3a).
ABSTRACT
Thiolysis of a variety of 1,2-epoxides in water at 30 degrees C and pH 7.0 is strongly accelerated by ZnCl(2) (10 mol %) except when amino- and carboxythiophenol are used. The aqueous medium and the catalyst were recovered and reused in various runs without affecting the efficiency of the process.
