Straightforward and efficient synthesis of 3-benzyloxy-4-bromopicolinate ester and 3-benzyloxy-5-bromopicolinate ester, common building blocks for pharmaceuticals and agrochemicals

Ethyl acetate as an acetyl source and solvent for acetylation of alcohols by KOH

A KOH mediated mild, efficient, convenient and gram-scalable protocol for the acetylation of alcohols with EtOAc as acetyl source and solvent. Various types of alcohols were successfully transformed into according acetylated products. Good to excellent yields were offered by primary alcohols and low to moderate yields were offered by secondary alcohols.

Oxime-mediated in vitro reactivation kinetic analysis of organophosphates-inhibited human and electric eel acetylcholinesterase

Organophosphate (OP)-based pesticides and nerve agents are highly toxic compounds which interrupt the catalytic mechanism of acetylcholinesterase (AChE) by phosphorylating the hydroxyl moiety of serine residue. The inhibited enzyme can be reactivated by the nucleophilic action of oxime reactivators. To analyze the effect of different AChE sources on reactivation efficacy of reactivators, several in vivo studies have carried out using variety of AChE sources like pig, rat and monkey. Investigations on species differences provide a better insight for the development of new reactivators. Hence, present study was mainly targeted on comparative analysis of the reactivation of electric eel and human AChE inhibited by different OP. A series of butene-linked bis-pyridinium mono oximes which vary in functional groups present at the second pyridinium ring have been examined against sarin, VX, tabun and ethyl-paraoxon-poisoned AChE. In case of tabun-inhibited AChEs, tested oximes were better than reference oximes. For VX-poisoned human AChE, reactivator K251 (kr2;1.51 mM (-) (1 )min (-) (1)) showed good reactivation efficacy with standard oximes. Studies stipulated that butene-linked oximes consisting of different functional moieties are good reactivators and found to have better efficacy to reactivate nerve agent-inhibited human AChE in comparison to eel AChE.

Synthesis and in vitro evaluation of donepezil-based reactivators and analogues for nerve agent-inhibited human acetylcholinesterase

Donepezil-based reactivators 1–3 show a better ability (8 fold higher) than pralidoxime to reactivate VX-hAChE, and oxime 2 is 5 to 11 fold more efficient than pralidoxime and HI-6 respectively to reactivate of VX-hBChE.

A selective orexin-1 receptor antagonist attenuates stress-induced hyperarousal without hypnotic effects

Orexins (OXs) are peptides produced by perifornical (PeF) and lateral hypothalamic neurons that exert a prominent role in arousal-related processes, including stress. A critical role for the orexin-1 receptor (OX1R) in complex emotional behavior is emerging, such as overactivation of the OX1R pathway being associated with panic or anxiety states. Here we characterize a brain-penetrant, selective, and high-affinity OX1R antagonist, compound 56 [N-({3-[(3-ethoxy-6-methylpyridin-2-yl)carbonyl]-3-azabicyclo[4.1.0]hept-4-yl}methyl)-5-(trifluoromethyl)pyrimidin-2-amine]. Ex vivo receptor binding studies demonstrated that, after subcutaneous administration, compound 56 crossed the blood-brain barrier and occupied OX1Rs in the rat brain at lower doses than standard OX1R antagonists GSK-1059865 [5-bromo-N-({1-[(3-fluoro-2-methoxyphenyl)carbonyl]-5-methylpiperidin-2-yl}methyl)pyridin-2-amine], SB-334867 [1-(2-methyl-1,3-benzoxazol-6-yl)-3-(1,5-naphthyridin-4-yl)urea], and SB-408124 [1-(6,8-difluoro-2-methylquinolin-4-yl)-3-[4-(dimethylamino)phenyl]urea]. Although compound 56 did not alter spontaneous sleep in rats and in wild-type mice, its administration in orexin-2 receptor knockout mice selectively promoted rapid eye movement sleep, demonstrating target engagement and specific OX1R blockade. In a rat model of psychological stress induced by cage exchange, the OX1R antagonist prevented the prolongation of sleep onset without affecting sleep duration. In a rat model of panic vulnerability (involving disinhibition of the PeF OX region) to threatening internal state changes (i.e., intravenous sodium lactate infusion), compound 56 attenuated sodium lactate-induced panic-like behaviors and cardiovascular responses without altering baseline locomotor or autonomic activity. In conclusion, OX1R antagonism represents a novel therapeutic strategy for the treatment of various psychiatric disorders associated with stress or hyperarousal states.

Design, synthesis and biological evaluation of novel tetrahydroacridine pyridine- aldoxime and -amidoxime hybrids as efficient uncharged reactivators of nerve agent-inhibited human acetylcholinesterase

A series of new uncharged functional acetylcholinesterase (AChE) reactivators including heterodimers of tetrahydroacridine with 3-hydroxy-2-pyridine aldoximes and amidoximes has been synthesized. These novel molecules display in vitro reactivation potencies towards VX-, tabun- and paraoxon-inhibited human AChE that are superior to those of the mono- and bis-pyridinium aldoximes currently used against nerve agent and pesticide poisoning. Furthermore, these uncharged compounds exhibit a broader reactivity spectrum compared to currently approved remediation drugs.