915237-87-5Relevant academic research and scientific papers
Visible light-promoted radical cyclization of silicon-tethered alkyl iodide and phenyl alkyne. An efficient approach to synthesize benzosilolines
Lin, Xinglong,Gan, Zubao,Lu, Ji,Su, Zhishan,Hu, Changwei,Zhang, Yuebao,Wu, Ya,Gao, Lu,Song, Zhenlei
supporting information, p. 6189 - 6192 (2016/05/19)
An efficient approach to synthesize benzosiloline has been developed using a visible light-promoted radical cyclization reaction of silicon-tethered alkyl iodide and phenyl alkyne.
Synthesis and reactivity of enediyne-nucleobase hybrids: Effect of intramolecular π-stacking
Roy, Snigdha,Bag, Subhendu Sekhar,Basak, Amit
supporting information, p. 8600 - 8611 (2012/10/29)
Three distinct classes of nucleobase-containing enediynes 1-9 with varying nature of the linker have been synthesized to explore the effect of π-stacking interaction in accelerating the rate of Bergman cyclization (BC). Chemical reactivity study, both experimental and computations demonstrated the important role that aromatic π-stacking interactions between the appended nucleobases within an enediyne frame play in lowering the activation barrier of Bergman cyclization.
Design, synthesis and inhibition activity of a novel cyclic enediyne amino acid conjugates against MPtpA
Chandra, Koushik,Dutta, Debajyoti,Mitra, Analava,Das, Amit K.,Basak, Amit
supporting information; experimental part, p. 3274 - 3279 (2011/06/25)
In course of studies towards the discovery of selective inhibitors of MPtpA, a novel cyclic endiyne malonamic acid has been designed and synthesized. The synthesis involves a crucial intramolecular Knoevenagel reaction. The compound displayed a reversible non-competitive inhibition against MPtpA with inhibition constant Ki of 22.5 μM. The enediyne acts as a recognition framework in inducing the inhibition and not as a reactive functional moiety. This was confirmed by comparing the inhibiting activity with that of the corresponding saturated cyclic non-enediyne analogue.
Conformationally gated fragmentations and rearrangements promoted by interception of the bergman cyclization through intramolecular H-abstraction: A possible mechanism of auto-resistance to natural enediyne antibiotics?
Baroudi, Abdulkader,Mauldin, Justin,Alabugin, Igor V.
supporting information; experimental part, p. 967 - 979 (2010/03/31)
A variety of fragmentations and rearrangements can follow Bergman cyclization in enediynes equipped with acetal rings mimicking the carbohydrate moiety of natural enediyne antibiotics of the esperamicine and calchiamicine families. In the first step of all these processes, intramolecular H-atom abstraction efficiently intercepts the p-benzyne product of the Bergman cyclization through a six-membered TS and transforms the p-benzyne into a new more stable radical. Depending on the substitution pattern and reaction conditions, this radical follows four alternative paths: (a) abstraction of an external hydrogen atom, (b) O-neophyl rearrangement which transposes O- and C-atoms of the substituent, (c) fragmentation of the O-C bond in the acetal ring, or (d) fragmentation with elimination of the appended acetal moiety as a whole. Experiments with varying concentrations of external H-atom donor (1,4-cyclohexadiene) were performed to gain further insight into the competition between intermolecular H-abstraction and the fragmentations. The Thorpe-Ingold effect in gem-dimethyl substituted enediynes enhances the efficiency of fragmentation to the extent where it cannot be prevented even by a large excess of external H-atom donor. These processes provide insight into a possible mechanism of unusual fragmentation of esperamicin A1 upon its Bergman cycloaromatization and lay foundation for a new approach for the conformational control of reactivity of these natural antitumor antibiotics. Such an approach, in conjunction with supramolecular constraints, may provide a plausible mechanism for resistance to enediyne antibiotics by the enediyne-producing microorganisms.
Reaction of ene-bis(phosphinylallenes): [2+2] versus [4+2] cycloaddition
Kitagaki, Shinji,Okumura, Yuki,Mukai, Chisato
, p. 10311 - 10320 (2007/10/03)
Reaction of ene-bis(phosphinylallenes), derived from ene-bis(propargyl alcohols) and chlorodiphenylphosphine, was investigated. Benzene-bridged bis(phosphinylallenes) exclusively gave intramolecular [2+2] cycloadducts in the presence of dimethyl fumarate
