13472-84-9Relevant academic research and scientific papers
GLP-1R AGONISTS AND USES THEREOF
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Page/Page column 64; 72, (2020/06/10)
Provided are compounds of Formula (I) and pharmaceutical compositions thereof, for use in, e.g. treating type 2 diabetes mellitus, pre-diabetes, obesity, non-alcoholic fatty liver disease, non-alcoholic steatohepatitis, and cardiovascular disease.
Substituted 3,4-pyridynes: Clean cycloadditions
Connon, Stephen J.,Hegarty, Anthony F.
, p. 1245 - 1249 (2007/10/03)
The stabilisation of 3,4-pyridyne (1) by an alkoxy group adjacent to the ring nitrogen is reported. The regioselective lithiation of 2-ethoxy- (14), 2-methoxy- (18), 2-isopropoxy- (19) and 6-isopropoxy- (26) -3-chloropyridines with tertbutyllithium at low temperatures, followed by elimination of lithium chloride affords 2- and 6-alkoxy-3,4-pyridynes. These species are trapped m situ with furan in a Diels-Alder reaction to give 5-8 in 66-89% yield, and do not give products typical of polymerisation or nucleophilic addition to the 3,4-pyridyne intermediates. As a comparison treatment of 3-chloropyridine with furan and LDA gives only 19% of adduct (4). We also report the novel use of the isopropoxy (rather than methoxy) group in these systems, which can act as a heteroatomic electron donating group which inhibits a-lithiation by tert-butyllithium because of its increased steric bulk. The Royal Society of Chemistry 2000.
Utilizing Acetyl Hypofluorite for Chlorination, Bromination, and Etherification of the Pyridine System
Hebel, David,Rozen, Shlomo
, p. 6298 - 6301 (2007/10/02)
Acetyl hypofluorite, which is easily made from F2, possesses a strong electrophilic fluorine.This electrophile is able to attach itself to the nitrogen atom of pyridine and activate the ring toward nucleophilic attacks.The ultimate elimination of HF results in an overall easy nucleophilic displacement of the hydrogen of the important 2-position .The nucleophiles used: Clδ-, Brδ-, ROδ-, originate from solvents such as CH2Cl2, CH2Br2, and various primary alcohols.Thus, 2-halo- or 2-alkoxypyridines were formed.The reaction conditions (room temperature, very short reaction times, and good yields) transform the task of direct substitution of the pyridine ring from an extremely difficult to a very easy procedure.
Reactions of Caesium Fluoroxysulphate with Pyridine
Stavber, Stojan,Zupan, Marko
, p. 775 - 776 (2007/10/02)
Pyridine readily reacts with CsSO4F in various solvents at room temperature producing a mixture of up to three products (2-fluoropyridine, 2-pyridyl fluorosulfonate and 2-chloro or 2-alkoxypyridine), their distribution strongly depending on the solvent used.Reaction of 3-chloropyridine with CsSO4F in methanol leads regioselectively to 2-methoxy-3-chloropyridine, while 3-methylpyridine was converted into 2-methoxy-3-methyl and 2-methoxy-5-methylpyridine in a 2:1 relative ratio.
NEW REACTIONS OF PYRIDINES AND TOTAL SYNTHESIS OF THE FUNGAL TOXIN ORELLANINE
Tiecco, Marcello
, p. 1009 - 1020 (2007/10/02)
Dihalogenated pyridines react easily with sulphur nucleophiles, in dipolar aprotic solvents (DMF), to afford the products of mono- or of bis-substitution depending on the experimental conditions.On the contrary, with oxygen nucleophiles the bis-substituted products can be obtained only with some particular substrates.A new and efficient procedure to effect the homo-coupling of halogenoarenes will be presented.This reaction, wich occurs under the influence of low-valent nickel complexes, allowed us to effect the total synthesis of Orellanine, the lethal toxin of Cortinarius orellanus mushroom, as well as the syntheses of its decompositionproducts Orellinine and Orelline.The chemical properties of these three products and their behaviour towards UV irradiation will be presented and discussed.
THE REACTIONS OF SOME HALOGENATED PYRIDINES WITH METHOXYDE AND METHANETHIOLATE IONS IN DIMETHYLFORMAMIDE
Testaferri, Lorenzo,Tiecco, Marcello,Tingoli, Marco,Bartoli, Donatella,Massoli, Alberto
, p. 1373 - 1384 (2007/10/02)
The reactions of 2,6- and 2,5-dibromopyridines and of 2,3- and 3,5-dichloropyridines with sodium isopropanethiolate and methanethiolate afforded the products of mono- or of bis-substitution depending on the experimental conditions.The same pyridines reacted with sodium methoxide to give good yields of the mono-substituted products; bis-substitution occurred easily only in the case of the 2,6-dibromo- and of the 3,5-dichloropyridine.The syntheses of some methoxy thiomethoxypyridine, starting from the halogeno methoxypyridines or from the halogeno thiomethoxypyridines are also described.The bis-(alkylthio)pyridines can be fragmented by sodium in HMPA to give the bis(mercapto)pyridines.
