2723-38-8Relevant articles and documents
Photoenzymatic Generation of Unstabilized Alkyl Radicals: An Asymmetric Reductive Cyclization
Clayman, Phillip D.,Hyster, Todd K.
supporting information, p. 15673 - 15677 (2020/10/18)
Flavin-dependent "ene"-reductases can generate stabilized alkyl radicals when irradiated with visible light; however, they are not known to form unstabilized radicals. Here, we report an enantioselective radical cyclization using alkyl iodides as precursors to unstabilized nucleophilic radicals. Evidence suggests this species is accessed by photoexcitation of a charge-transfer complex that forms between flavin and substrate within the protein active site. Stereoselective delivery of a hydrogen atom from the flavin semiquinone to the prochiral radical formed after cyclization provides high levels of enantioselectivity across a variety of substrates. Overall, this transformation demonstrates that photoenzymatic catalysis can address long-standing selectivity challenges in the radical literature.
NOVEL AZAINDOLE INHIBITORS OF MTP AND ApoB
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Page/Page column 78, (2008/06/13)
The present invention relates to 7-azaindole-based compounds, to processes for the preparation thereof, to pharmaceutical compositions com-prising them, and to the use thereof in the preparation of medicaments that are useful as inhibitors of MTP and of A
Cyclopentadienylideneethenone: Pyrolytic Generation and Argon Matrix Infrared Spectroscopic Study
Brown, Roger F. C.,Browne, Neil R.,Coulston, Karen J.,Eastwood, Frank W.,Irvine, Margaret J.,et al.
, p. 1321 - 1344 (2007/10/02)
Two previously reported pyrolytic precursors for cyclopentadienylideneethenone (4) and benzyne produced two strong infrared bands attributable to ketene type compounds when their pyrolysates were examined by argon matrix isolation spectroscopy.To determine which band should be assigned to (4), four new precursors for (4) and benzyne and two analogues labelled with 13C at the carbonyl group have been synthesized.Precursors (8) and (14) are respectively a caged system and a bridged system bearing a mixed anhydride with trifluoroacetic acid.Flash vacuum pyrolysis of (8) and (14) at 600-700 deg with trapping at 77 K gave pyrolysates which contaned biphenylene.Pyrolysis of (8) and (14) at 600-700 deg in a stream of argon followed by deposition as an argon matrix at about 10 K showed that both produced a pyrolysate absorbing at 2089 cm-1 assigned to (4).Precursors (24) and (25) and the previously reported (18) and (27) are Meldrum's acid derivatives designed to yield the hypothetical cyclopentadienylide Meldrum's acid (19) by cage fission or retro-Diels-Alder reaction.They all gave their biphenylene on flash vacuum pyrolysis at 600-700 deg and their pyrolysates in argon matrices showed absorption both at 2089 cm-1 due to (4) and at 2225 cm-1 due to an unidentified ketene.The frequency shift resulting from substitution of 13C in the carbonyl group (52 cm-1) is in accordance with the assignment of the 2089 cm-1 band to (4).The pyrolysates from precursors (8a), (14), (18a), (25) and (27) were allowed to react with methanol and the resulting mixtures were hydrogenated.In all cases methyl cyclopentylacetate was obtained.
