134005-20-2Relevant articles and documents
Infrared Spectra of (Z)- And (E)-?C2H3C(CH3)I Radicals Produced upon Photodissociation of (Z)- And (E)-(CH2I)HC═C(CH3)I in Solid para-Hydrogen
Chen, Kuang-Po,Haupa, Karolina Anna,Lee, Yuan-Pern,Li, Yaw-Kuen
, p. 5887 - 5895 (2020)
Ozonolysis of isoprene to produce Criegee intermediates such as methyl vinyl ketone oxide (MVKO), C2H3C(CH3)OO, is an important process in atmospheric chemistry. MVKO was recently produced and identified in laboratories after photolysis of a gaseous mixture of 1,3-diiodo-but-2-ene, (CH2I)HC═C(CH3)I, and O2, but the mechanism of its formation remains unexplored. We synthesized pure (Z)- and (E)-1,3-diiodo-but-2-ene and measured their distinct IR spectra. Upon irradiation at 280 nm of (Z)- and (E)-1,3-diiodo-but-2-ene in solid p-H2 at 3.3 K, the fission of the terminal C - I bond yields (Z)- and (E)-3-iodo-but-2-en-1-yl [?C2H3C(CH3)I] radicals, respectively. These radicals were characterized with infrared absorption lines at 2962.4, 1423.8, 1265.3, 1120.9/1127.0, 921.4/922.3, and 792.5/791.7 cm-1, and 16 additional weaker lines for (Z)-?C2H3C(CH3)I and 1405.2, 1208.2, 1106.0/1103.9, 934.2/933.4, and 785.1/784.9 cm-1 and five additional weaker ones for (E)-?C2H3C(CH3)I. The assignments were derived according to behavior on secondary photolysis and comparison of the vibrational wavenumbers and the IR intensities of observed lines with those calculated with the B2PLYP-D3/aug-cc-pVTZ-pp method. These observations confirmed that only the terminal I atom, not the central one, was photodissociated at 280 nm and, in solid p-H2, the excess energy after photodissociation induced no change in conformation. These new spectra of ?C2H3C(CH3)I radicals can provide valuable information for the understanding of the mechanism of formation of Criegee intermediate MVKO from the source reaction of photolysis of (CH2I)HC═C(CH3)I in O2 in the laboratory.
Optimized synthesis and antiproliferative activity of desTHPdactylolides
Chen, Guanglin,Wang, Rubing,Vue, Bao,Patanapongpibul, Manee,Zhang, Qiang,Zheng, Shilong,Wang, Guangdi,White, James D.,Chen, Qiao-Hong
, p. 3514 - 3520 (2018/05/24)
Dactylolide and certain analogues are attractive targets for study due to their structural resemblance to zampanolide, a very promising anticancer lead compound and a unique covalent-binding microtubule stabilizing agent. The primary goal of this project is identification and synthesis of simplified analogues of dactylolide that would be easier to prepare and could be investigated for antiproliferative activity in comparison with zampanolide. Extension of Almann's concept of a simplified zampanolide analogue to dactylolide in the form of desTHPdactylolide was attractive not only for reasons of synthetic simplification but also for the prospect that analogues of dactylolide could be prepared in both (17S) and (17R) configurations. Since Altmann's overall yield for the six-step procedure leading to the C9–C18 fragment of desTHPdactylolide was only 8.7%, a study focused on optimized synthesis and antiproliferative evaluation of each enantiomer of desTHPdactylolide was initiated using Altmann's route as a framework. To this end, two optimized approaches to this fragment C9–C18 were successfully developed by us using allyl iodide or allyl tosylate as the starting material for a critical Williamson ether synthesis. Both (17S) and (17R) desTHPdactylolides were readily synthesized in our laboratory using optimized methods in yields of 37–43%. Antiproliferative activity of the pair of enantiomeric desTHPdactylolides, together with their analogues, was evaluated in three docetaxel-sensitive and two docetaxel-resistant prostate cancer cell models using a WST-1 cell proliferation assay. Surprisingly, (17R) desTHPdactylolide was identified as the eutomer in the prostate cancer cell models. It was found that (17S) and (17R) desTHPdactylolide exhibit equivalent antiproliferative potency towards both docetaxel-sensitive (PC-3 and DU145) and docetaxel-resistant prostate cancer cell lines (PC-3/DTX and DU145/DTX).
Synthesis of epothilones, intermediates thereto and analogues thereof
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, (2008/06/13)
The present invention provides convergent processes for preparing epothilones, desoxyepothilones, and analogues thereof. The present invention further provides novel compositions and methods for the treatment of cancer and additionally provides methods for the treatment of cancer which has developed a multi-drug phenotype.
