20637-03-0Relevant articles and documents
Synthesis of 2-Substituted Cyclobutanones by a Suzuki Reaction and Dephosphorylation Sequence
Koudelka, Jakub,Tobrman, Tomá?
, p. 3260 - 3269 (2021/06/25)
We report a novel process for the preparation of 2-substituted cyclobutanones. Such a method relies on the cross-coupling reaction of bromocyclobutenyl diethyl phosphate with either boronic acids or organozinc reagents. Dephosphorylation of the prepared 2-substituted cyclobutenyl phosphates affords 2-substituted cyclobutanones. We observed that the course of the dephosphorylation reaction depends on the properties of the substituents found on the cyclobutene nucleus. The presence of groups capable of stabilizing the negative charge is necessary for ring opening of cyclobutanones. The scope of the reported process for the preparation of 2-substituted cyclobutanones has also been extended to the preparation of cyclobutenyl sulfides.
Oxadiazole derivatives as S1P1 receptor agonists
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Page/Page column 35, (2010/08/07)
New compounds having the chemical structure of formula (I) or pharmaceutically acceptable salts or N-oxides thereof wherein A is selected from the group consisting of -N-, -O- and -S-; B and C independently are selected from the group consisting of -N- and -O-, with the proviso that at least two of A, B and C are nitrogen atoms; G1 is selected from the group consisting of nitrogen atoms and -CRC- groups, wherein RC represents a hydrogen atom, a halogen atom, a C1-4 alkyl group or a C1-4 alkoxy group; R1 is selected from the group consisting of hydrogen atoms, C1-4 alkyl groups, C1-4 alkoxy groups, C3-4 cycloalkyl groups, and -NRdRe groups wherein Rd and Re are independently selected from hydrogen atoms and C1-4 alkyl groups; R2 and R3 are independently selected from the group consisting of hydrogen atoms and C1-4 alkyl groups; R4, R5 and R7 are independently selected from the group consisting of hydrogen atoms, halogen atoms, C1-4 alkyl groups, C1-4 alkoxy groups and C1-4 haloalkyl groups; R6 represents a C1-4 alkyl group or a C1-4 hydroxyalkyl group; or R6 is selected from the group consisting of -S(O)2-NRaRb groups, -(CRfRg)n-(CRhRi)x-(CRjRk)y-NRaRb groups, -(CH2)n-NRaRb groups, -O-(CH2)n-NRaRb groups, -(CH2)n-COOH groups, -(CH2)n-NRa-CO-Rb' groups, -(CH2)n-NRa-(CH2)p-(NH)q-SO-CH3 groups and -(CH2)n-CO-NRaRb groups, wherein n, p, x and y are each independently integers from 0 to 3, q is 0 or 1, Rf, Rg, Rh, Ri, Rj and Rk independently represent hydrogen atoms or halogen atoms, Rb' is selected from the group consisting of methylsulphonyl groups, C1-4 alkyl groups, C1-4 hydroxyalkyl groups, C1-4 carboxyalkyl groups, and C1-4 haloalkyl groups; Ra and Rb are independently selected from the group consisting of hydrogen atoms, methylsulphonyl groups, C1-4 alkyl groups, C1-4 hydroxyalkyl groups, C1-4 carboxyalkyl groups, and C1-4 haloalkyl groups, or Ra and Rb together with the nitrogen atom to which they are attached form a 4 to 6 membered, saturated heterocyclic group, which contains, as heteroatoms, one or two nitrogen atoms and which is substituted by a carboxyl group or a C1-4 carboxyalkyl group; or Rc together with R6 form a C5-8 carbocyclic ring optionally substituted by - NHR' wherein R' represents a hydrogen atom or a 61-4 carboxyalkyl group.
