Synthetic studies towards 4,10-diaza-1,7-dioxaspiro[5.5]undecanes: access to 3-aza-6,8-dioxabicyclo[3.2.1]octan-2-one and 2H-1,4-oxazin-3(4H)-one frameworks
摘要:
Synthetic approaches towards 4,10-diaza-1,7-dioxaspiro[5.5] undecanes starting from 1,3-dichloroacetone and solketal derivatives are explored. The method relies on the preparation of a key bis-substituted dihydroxy-protected oxime, which would undergo a final acidic deprotection-spiroacetalization process. Although the desired diazaspiroketal framework could not be obtained, our conditions led to the unexpected 3-aza-6,8-dioxabicyclo[3.2.1] octan-2-one 18 or to the oxazinone 32 in good yields. (c) 2007 Elsevier Ltd. All rights reserved.
Synthetic studies towards 4,10-diaza-1,7-dioxaspiro[5.5]undecanes: access to 3-aza-6,8-dioxabicyclo[3.2.1]octan-2-one and 2H-1,4-oxazin-3(4H)-one frameworks
摘要:
Synthetic approaches towards 4,10-diaza-1,7-dioxaspiro[5.5] undecanes starting from 1,3-dichloroacetone and solketal derivatives are explored. The method relies on the preparation of a key bis-substituted dihydroxy-protected oxime, which would undergo a final acidic deprotection-spiroacetalization process. Although the desired diazaspiroketal framework could not be obtained, our conditions led to the unexpected 3-aza-6,8-dioxabicyclo[3.2.1] octan-2-one 18 or to the oxazinone 32 in good yields. (c) 2007 Elsevier Ltd. All rights reserved.
Synthesis, and In vitro and In vivo muscarinic pharmacological properties of a series of 1,6-Dihydro-5-(4 H )-pyrimidinone oximes
作者:Ralf Plate、Marc J.M. Plaum、Peter Pintar、Christan G. Jans、Thijs de Boer、Fred A. Dijcks、Ge Ruigt、John S. Andrews
DOI:10.1016/s0968-0896(98)00074-1
日期:1998.9
A series of 1,6-dihydro-5-(4H)-pyrimidinone oxime derivatives I was synthesized (Scheme 1, Tables 1 and 2) and tested for muscarinic activity (Table 3) in receptor binding assays using [H-3]-oxotremorine-M (Oxo-M) and [H-3]-pirenzepine pirenzepine (Pz) as ligands. Potential muscarinic agonistic or antagonistic properties of the compounds were determined using binding studies that measured their potencies to inhibit the binding of Oxo-M and Pz. Preferential inhibition of Oxo-M binding was used as an indicator for potential muscarinic agonistic properties; this potential was confirmed in functional studies on isolated organs. The series produced a wide range of active compounds with differing degrees of selectivity in M-1, M-2, and M-3 functional models. Several compounds that have mixed agonist/antagonist profiles were able to reduce cholinergic-related cognitive impairments in models of mnemonic function. Substitutions (I, e.g. R-2 or R-3 = Me) at the 1,6-dihydro-5-(4H)pyrimidine ring disrupted binding and efficacy, whereas systematic variation of the oximes substituent R1 resulted in various degrees of potency and selectivity dependent on the nature of the substitution. (C) 1998 Elsevier Science Ltd. All rights reserved.
Synthetic studies towards 4,10-diaza-1,7-dioxaspiro[5.5]undecanes: access to 3-aza-6,8-dioxabicyclo[3.2.1]octan-2-one and 2H-1,4-oxazin-3(4H)-one frameworks
Synthetic approaches towards 4,10-diaza-1,7-dioxaspiro[5.5] undecanes starting from 1,3-dichloroacetone and solketal derivatives are explored. The method relies on the preparation of a key bis-substituted dihydroxy-protected oxime, which would undergo a final acidic deprotection-spiroacetalization process. Although the desired diazaspiroketal framework could not be obtained, our conditions led to the unexpected 3-aza-6,8-dioxabicyclo[3.2.1] octan-2-one 18 or to the oxazinone 32 in good yields. (c) 2007 Elsevier Ltd. All rights reserved.