1694-31-1Relevant articles and documents
Chemoselectivity in the Reactions of Acetylketene and Acetimidoylketene: Confirmation of Theoretical Predictions
Birney, David M.,Xu, Xiaolian,Ham, Sihyun,Huang, Xiaomeng
, p. 7114 - 7120 (1997)
Acetylketene (1) was generated by flash pyrolysis of 2,2,6-trimethyl-4H-1,3-dioxin-4-one (6). The selectivities of 1 toward a number of representative functional groups were measured for the first time in a series of competitive trapping reactions. The trend in reactivities toward 1 follows the general order amines > alcohols aldehydes ≈ ketones and can be rationalized by considering both the nucleophilicity and the electrophilicity of the reacting species. Alcohols show significant selectivity based on steric hindrance, with MeOH ≈ 1° > 2° > 3°. These selectivities are consistent with the activation energies and the pseudopericyclic transition structure previously calculated for the addition of water to formylketene. The results, presented here, of ab initio transition structure calculations for the addition of ammonia to formylketene are qualitatively consistent with the experimental trends as well. N-Propylacetacetimidoylketene (2) was generated by the solution pyrolysis of tert-butyl N-propyl-3-amino-2-butenoate (9a) and showed similar selectivity toward alcohols as opposed to ketones and similar steric discrimination toward alcohols. This is again in agreement with previous ab initio calculations. Taken together, these experimental trends in the reactivities of both 1 and 2 toward a variety of reagents provide strong, although indirect support for the planar, pseudopericyclic transition structures for these reactions which are predicted by ab initio calculations.
PORPHYRINS. 18. SYNTHESIS OF OCTAPROPYLPORPHYRIN BY THE METHOD OF MONOPYRROLE CYCLOTETRAMERIZATION OF 5-CARBOXY-2-METHOXYMETHYL-3,4-DIPROPYLPYRROLE. INVESTIGATION OF THE THERMOLYSIS OF meso-N-METHYLFORMALDIMINEOCTAPROPYLPORPHYRIN
Shul'ga, A. M.,Ponomarev, G. V.
, p. 748 - 753 (1984)
The synthesis of octapropylporphyrin on the basis of 5-carboxy-2-methoxymethyl-3,4-dipropylpyrrole was realized.It was demonstrated that in the thermolysis of meso-N-methylformaldimineoctapropylporphyrin, 31,51-cyclo-31-ethylidene- and 31,51-cyclo-31-ethyl-51-(N-methylimine) derivatives are also formed in addition to 31,51-cyclo-31-ethylheptapropylporphyrin.
Csp3-H monofluoroalkenylation via stereoselective C-F bond cleavage
Hu, Binjing,Hu, Ying,Li, Jie,Liu, Xingchen,Ren, Zhouyang
supporting information, p. 2734 - 2737 (2022/03/02)
A practical nickel- and photoredox-catalyzed Csp3-H monofluoroalkenylation through chelation-assisted Csp2-F bond cleavage of gem-difluoroalkenes for the synthesis of stereodefined tetrasubstituted fluoroalkenes has been developed. Moreover, the gem-difluoroalkenes can also undergo photoredox-catalyzed cascade twofold C-F diaminomethylation. This journal is
Visible-light-driven radical 1,3-addition of selenosulfonates to vinyldiazo compounds
Li, Weiyu,Zhou, Lei
supporting information, p. 6652 - 6658 (2021/09/10)
Herein, we report a visible-light-driven radical 1,3-selenosulfonylation of vinyldiazo compounds with selenosulfonates, providing various γ-seleno allylic sulfones in good yields. This photochemical reaction was carried out at room temperature in an open flask using ethyl acetate as the solvent without any photocatalysts or additives. The control experiments corroborated that the 1,3-addition proceeded via a radical-chain propagation process. The synthetic applications of the resulting products were demonstrated by deselenization, reduction, bromination and allylation.
Design, synthesis, and molecular docking study of new monastrol analogues as kinesin spindle protein inhibitors
El-Hamamsy, Mervat H.,Sharafeldin, Nabaweya A.,El-Moselhy, Tarek F.,Tawfik, Haytham O.
, (2020/06/03)
Lung, colorectal, and breast cancers are the top three types of cancer by incidence and are responsible for one-third of the cancer incidence and mortality. A series of 18 3,4-dihydropyrimidine analogues bearing a 1,2-methylenedioxybenzene component at position 4 with diverse side chains at positions 5 and 6 was designed and synthesized as inhibitors of the Eg5 kinesin enzyme. Target compounds were screened for their anticancer activity according to the NCI-USA protocol toward a panel of 60 cancer cell lines. Compounds 12a and 12b displayed the best antiproliferation activity against many cell lines. Interestingly, compound 12a displayed lethal effects against non-small-cell lung cancer NCI-H522 cells (?42.26%) and MDA-MB-468 breast cancer cells (?1.10%) at a single-dose assay concentration of 10?5 M. Compounds 11c, 11d, 11g, 12a–d, 13, 15, and 18a were assayed against the kinesin enzyme, with IC50 values ranging from 1.2 to 18.71 μM, which were more potent compared with monastrol (IC50 = 20 μM). Cell cycle analysis of NCI-H522 cells treated with compound 12a showed cell cycle arrest at the G2/M phase. Furthermore, the expression levels of active caspase-3 and -9 were measured. A molecular docking study was performed for some demonstrative compounds as well as monastrol docked into the allosteric binding site of the kinesin spindle protein.
