107978-04-1Relevant articles and documents
Enantioselective Protonation of Cyclic Carbonyl Ylides by Chiral Lewis Acid Assisted Alcohols
Arisue, Kaoru,Esaki, Hiroyoshi,Fukushima, Kazuaki,Kikuchi, Ayaka,Suga, Hiroyuki,Toda, Yasunori,Yoshida, Takayuki
, p. 10578 - 10582 (2021)
Chiral Lewis acid-catalyzed asymmetric alcohol addition reactions to cyclic carbonyl ylides generated from N-(α-diazocarbonyl)-2-oxazolidinones featuring a dual catalytic system are reported. Construction of a chiral quaternary heteroatom-substituted carb
Direct Catalytic Desaturation of Lactams Enabled by Soft Enolization
Chen, Ming,Dong, Guangbin
, p. 7757 - 7760 (2017)
A direct catalytic method is described for the α,β-desaturation of N-protected lactams to their conjugated unsaturated counterparts under mildly acidic conditions. The reaction is consistently operated at room temperature and tolerates a wide range of functional groups, showing reactivity complementary to that of prior desaturation methods. Lactams with various ring sizes and substituents at different positions all reacted smoothly. The synthetic utility of this method is demonstrated in a concise synthesis of Rolipram. In addition, linear amides also prove to be competent substrates, and the phthaloyl-protected product serves as a convenient precursor to access various conjugated carboxylic acid derivatives. Strong bases are avoided in this desaturation approach, and the key is to merge soft enolization with a Pd-catalyzed oxidation process.
N-Hydroxybenzimidazole as a structurally modifiable platform forN-oxyl radicals for direct C-H functionalization reactions
Hatanaka, Miho,Jiang, Julong,Maruoka, Keiji,Matsumoto, Akira,Sakamoto, Ryu,Sakurai, Shunya,Tsuzuki, Saori,Yoshii, Tomomi
, p. 5772 - 5778 (2020/06/22)
Methods for direct functionalization of C-H bonds mediated byN-oxyl radicals constitute a powerful tool in modern organic synthesis. While severalN-oxyl radicals have been developed to date, the lack of structural diversity for these species has hampered further progress in this field. Here we designed a novel class ofN-oxyl radicals based onN-hydroxybenzimidazole, and applied them to the direct C-H functionalization reactions. The flexibly modifiable features of these structures enabled facile tuning of their catalytic performance. Moreover, with these organoradicals, we have developed a metal-free approach for the synthesis of acyl fluoridesviadirect C-H fluorination of aldehydes under mild conditions.
Trimethylphosphine-Promoted Alcoholysis of α,β-Unsaturated Imides and α,β-Unsaturated Esters
Sato, Haruka,Hosokawa, Seijiro
, p. 1343 - 1349 (2018/01/27)
α,β-Unsaturated imides and α,β-unsaturated esters were found to undergo alcoholysis in the presence of trimethylphosphine. The reaction is initiated by nucleophilic addition of trimethylphosphine to the double bond of the α,β-unsaturated carbonyl compound. Saturated imides also undergo the alcoholysis in the presence of the corresponding α,β-unsaturated imide.
Design, synthesis, and biological evaluation of oxazolidone derivatives as highly potent N-acylethanolamine acid amidase (NAAA) inhibitors
Ren, Jie,Li, Yuhang,Ke, Hongwei,Li, Yanting,Yang, Longhe,Yu, Helin,Huang, Rui,Lu, Canzhong,Qiu, Yan
, p. 12455 - 12463 (2017/03/11)
N-Acylethanolamine-hydrolyzing acid amidase (NAAA) is a lysosomal enzyme that catalyzes the hydrolysis of endogenous fatty acid ethanolamides (FAEs), such as N-palmitoylethanolamide (PEA). PEA exhibits anti-inflammatory and analgesic activities by engaging peroxisome proliferator-activated receptor α (PPAR-α). Preventing PEA degradation by inhibition of NAAA has been proposed as a novel strategy for the treatment of inflammation and pain. In the present study, we reported the discovery of the oxazolidone derivative as a novel scaffold for NAAA inhibitors, and studied the structure-activity relationship (SAR) by modification of the side chain and terminal lipophilic substituents. The results showed that the link chain length of C5, straight and saturated linkages were the preferred shape patterns for NAAA inhibition. Several nanomolar NAAA inhibitors were described, including 2f, 3h, 3i and 3j with IC50 values of 270 nM, 150 nM, 100 nM and 190 nM, respectively. Enzymatic degradation studies suggested that 2f inhibited NAAA in a selective, noncompetitive and reversible pattern. Moreover, 2f showed high anti-inflammatory and analgesic activities after systemic and oral administration.
Direct N-acylation of lactams, oxazolidinones, and imidazolidinones with aldehydes by Shvo's catalyst
Zhang, Jian,Hong, Soon Hyeok
supporting information, p. 4646 - 4649 (2012/10/29)
Direct N-acylation of lactams, oxazolidinones, and imidazolidinones was achieved with aldehydes by Shvo's catalyst without using any other stoichiometric reagent. The N-acylations with α,β-unsaturated aldehydes were achieved with excellent yields.
Rapid assembly of matrix metalloprotease inhibitors using click chemistry
Wang, Jun,Uttamchandani, Mahesh,Li, Junqi,Hu, Mingyu,Yao, Shao Q.
, p. 3821 - 3824 (2007/10/03)
A panel of 96 metalloprotease inhibitors was assembled using "click chemistry" by reacting eight zinc-binding hydroxamate warheads with 12 azide building blocks. Screens of the bidentate compounds against representative metalloproteases provided discerning inhibition fingerprints, revealing compounds with low micromolar potency against MMP-7. The relative ease and convenience of the strategy in constructing focused chemical libraries for rapid in situ screening of MMPs is thereby demonstrated.
Stereoselective synthesis of (E)-trisubstituted α,β-unsaturated amides and acids
Feuillet, Fred J. P.,Cheeseman, Matt,Mahon, Mary F.,Bull, Steven D.
, p. 2976 - 2989 (2007/10/03)
Potassium alkoxides of N-acyl-oxazolidin-2-one-syn-aldols undergo stereoselective elimination reactions to afford a range of trisubstituted (E)-αβ-unsaturated amides in >95% de, that may be subsequently converted into their corresponding (E)-αβ-unsaturated acids or (E)-αβ-unsaturated oxazolines in good yield. syn-Aldols derived from αβ-unsaturated aldehydes gave their corresponding trisubstituted (E)-αβ-unsaturated-amides with poorer levels of diastereocontrol, whilst there was a similar loss in (E)-selectivity during elimination of syn-aldols derived from chiral aldehydes. These elimination reactions proceed via rearrangement of the potassium alkoxide of the syn-aldol to a 1,3-oxazinane-2,4-dione enolate intermediate that subsequently eliminates carbon dioxide to afford a trisubstituted (E)-αβ-unsaturated amide. The (E)-selectivity observed during the ElcB-type elimination step has been rationalised using a simple conformational model that employs a chair-like transition state to explain the observed stereocontrol. The Royal Society of Chemistry 2005.
Enantioselective synthesis of dimethyl 3,4-diphenyladipate by electroreductive hydrocoupling of chiral N-trans-cinnamoyl-2-oxazolidones
Kise, Naoki,Echigo, Mitsuaki,Shono, Tatsuya
, p. 1897 - 1900 (2007/10/02)
Dimethyl (3R,4R)- and (3S,4S)-diphenyladipate were synthesized enantioselectively by electroreductive intermolecular hydrocoupling of chiral N-trans-cinnamoyl-2-oxazolidones and subsequent methanolysis.
