143747-65-3Relevant academic research and scientific papers
Enantioselective organocatalytic iodination-initiated Wagner-Meerwein rearrangement
Romanov-Michailidis, Fedor,Guenee, Laure,Alexakis, Alexandre
, p. 5890 - 5893 (2013)
The present manuscript describes a high-yielding enantioselective semipinacol transposition, initiated by an electrophilic iodination event. The title transformation makes use of the anionic phase-transfer catalysis (PTC) paradigm for chirality induction. Thus, when combined appropriately, the insoluble cationic iodinating reagent S9 and the lipophilic phosphoric acid L9 act as an efficient source of chiral iodine that performs the semipinacol transposition of strained allylic alcohols A x to β-iodo spiroketones Bx in good yields and with high levels of diastereo- and enantio-induction. The product β-iodo spiroketones could be derivatized stereospecifically and without stereoerosion, giving rise to products inaccessible directly from a semipinacol rearrangement.
Enantioselective halogenative semi-pinacol rearrangement: Extension of substrate scope and mechanistic investigations
Romanov-Michailidis, Fedor,Romanova-Michaelides, Maria,Pupier, Marion,Alexakis, Alexandre
supporting information, p. 5561 - 5583 (2015/03/30)
The present Full Paper article discloses a survey of our recent results obtained in the context of the enantioselective halogenation-initiated semi-pinacol rearrangement. Commencing with the fluorination/semi-pinacol reaction first and moving to the heavier halogens (bromine and iodine) second, the scope and limitations of the halogenative phase-transfer methodology will be discussed and compared. An extension of the fluorination/semi-pinacol reaction to the ring-expansion of five-membered allylic cyclopentanols will be also described, as well as some preliminary results on substrates prone to desymmetrization will be given. Finally, the present manuscript will culminate with a detailed mechanistic investigation of the canonical fluorination/semi-pinacol reaction. Our mechanistic discussion will be based on in situ reaction progress monitoring, complemented with substituent effect, kinetic isotopic effect and non-linear behaviour studies.
Structure-Activity Studies on Benzhydrol-Containing Nipecotic Acid and Guvacine Derivatives as Potent, Orally-Active Inhibitors of GABA Uptake
Pavia, Michael R.,Lobbestael, Sandra J.,Nugiel, David,Mayhugh, Daniel R.,Gregor, Vlad E.,et al.
, p. 4238 - 4248 (2007/10/02)
The introduction of lipophilic groups onto the ring nitrogen of nipecotic acid and guvacine, two known GABA uptake inhibitors, afforded potent, orally-active anticonvulsant drugs.A series of compounds is reported which explores the structure-activity relationships (SAR) in this series.Among the areas explored: side-chain SAR (aromatic-, heterocyclic-, and tricyclic-containing side chains) and modifications to the tetrahydropyridine ring.The benzhydrol ether-containing side chains afforded the most potent compounds with several exhibiting in vitro IC50 values for GABA uptake of 1 μM (including 5, Table I; 37, 43, Table IV; and 44, Table V).Compound 44 was selected for extensive evaluation and subsequently progressed to Phase 1 clinical trials with severe adverse effects seen after single dose administration to humans.
