- Stabilised 2,3-pyridyne reactive intermediates of exceptional dienophilicity
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The enhanced dienophilicity of 4-methoxy, 4-aryloxy and 4-thiophenoxy analogues 6-9 of 2,3-pyridyne (2) relative to 2 itself is reported. The regioselective lithiation of 4-alkoxy-(22, 23 and 25) and 4-thiophenoxy-2- chloropyridme (24) at low temperatures, followed by elimination of lithium chloride affords 4-alkoxy- and 4-thiophenoxypyridynes, which can be trapped in situ in a [4+2] cycloaddition reaction with furan to give endoxides 28-31 in moderate to good yields (25-58%). In contrast, precursors with a hydrogen (18) or methyl (12) substituent at C-4 give no evidence for pyridyne formation under these conditions. Attempts to generate 6-isopropoxy-2,3-pyridyne (10) from the low-temperature lithiation of 2-chloro-6-isopropoxypyridine were unsuccessful due to the instability of the 2-chloro-6-isopropoxy-5-lithiopyridine. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004.
- Connon, Stephen J.,Hegarty, Anthony F.
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- GLUCOKINASE ACTIVATORS
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Provided are compounds of formula I that are useful in the treatment and/or prevention of diseases mediated by deficient levels of glucokinase activity, such as diabetes mellitus. Also provided are methods of treating or preventing diseases and disorders characterized by underactivity of glucokinase or which can be treated by activating glucokinase. (Formula I) wherein R2, L, Z, Y, G and R1 are as defined in the claims.
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Page/Page column 87
(2008/06/13)
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- Synthesis and biological activity of novel substituted pyridines and purines containing 2,4-thiazolidinedione
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A series of substituted pyridines and purines containing 2,4-thiazolidinedione were designed and synthesized from their corresponding pyridines and purines. These synthesized compounds (entry no. 6a-d, 12a-e, 18a-d, 23a-c) were evaluated for their effect on triglyceride accumulation in 3T3-L1 cells in vitro and their hypoglycemic and hypolipidemic activity in the genetically diabetic KKAy mice in vivo. On the basis of their biological activities, 5-(4-{2-[N-methyl-(5-phenyl-pyridin-2-yl)amino]ethoxy} benzyl)thiazolidine-2,4-dione (6d) was selected as a candidate for further pharmacological studies.
- Kim, Bok Young,Ahn, Joong Bok,Lee, Hong Woo,Kang, Sung Kwon,Lee, Jung Hwa,Shin, Jae Soo,Ahn, Soon Kil,Hong, Chung Il,Yoon, Seung Soo
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p. 433 - 447
(2007/10/03)
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- Diels-Alder cycloadditions of stabilised 2,3-pyridynes
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Investigation of electron donating substituents at C-4 on 2,3-pyridyne 1 stability has revealed a novel stabilisation of these reactive species by aryloxy and thiophenoxy groups leading to a relatively high yielding [4+2] cycloaddition between 4-(p-methoxyphenoxy)-2,3-pyridine and furan at low temperature.
- Connon, Stephen J.,Hegarty, Anthony F.
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p. 735 - 737
(2007/10/03)
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