- RhIII-Catalyzed Synthesis of Highly Substituted 2-Pyridones using Fluorinated Diazomalonate
-
A RhIII-catalyzed strategy was developed for the rapid construction of highly substituted 2-pyridone scaffolds using α,β-unsaturated oximes and fluorinated diazomalonate. The reaction proceeds through direct, site-selective alkylation based on migratory insertion and subsequent cyclocondensation. A wide substrate scope with different functional groups was explored. The requirement of fluorinated diazomalonate was explored for this transformation. The developed methodology was further extended with the synthesis of the bioactive compound.
- Das, Debapratim,Sahoo, Gopal,Biswas, Aniruddha,Samanta, Rajarshi
-
supporting information
p. 360 - 364
(2020/01/25)
-
- Novel Tetrahydroquinazolinamines as Selective Histamine 3 Receptor Antagonists for the Treatment of Obesity
-
The histamine 3 receptor (H3R) is a presynaptic receptor, which modulates several neurotransmitters including histamine and various essential physiological processes, such as feeding, arousal, cognition, and pain. The H3R is considered as a drug target for the treatment of several central nervous system disorders. We have synthesized and identified a novel series of 4-aryl-6-methyl-5,6,7,8-tetrahydroquinazolinamines that act as selective H3R antagonists. Among all the synthesized compounds, in vitro and docking studies suggested that the 4-methoxy-phenyl-substituted tetrahydroquinazolinamine compound 4c has potent and selective H3R antagonist activity (IC50 0.04 μM). Compound 4c did not exhibit any activity on the hERG ion channel and pan-assay interference compounds liability. Pharmacokinetic studies showed that 4c crosses the blood brain barrier, and in vivo studies demonstrated that 4c induces anorexia and weight loss in obese, but not in lean mice. These data reveal the therapeutic potential of 4c as an anti-obesity candidate drug via antagonizing the H3R.
- Kumar, Ajeet,Pasam, Venkata Reddy,Thakur, Ravi Kumar,Singh, Maninder,Singh, Kartikey,Shukla, Mahendra,Yadav, Anubhav,Dogra, Shalini,Sona, Chandan,Umrao, Deepmala,Jaiswal, Swati,Ahmad, Hafsa,Rashid, Mamunur,Singh, Sandeep K.,Wahajuddin, Muhammad,Dwivedi, Anil Kumar,Siddiqi, Mohammad Imran,Lal, Jawahar,Tripathi, Rama Pati,Yadav, Prem N.
-
p. 4638 - 4655
(2019/05/17)
-
- Manganese catalyzed α-methylation of ketones with methanol as a C1 source
-
The direct α-methylation of ketones with methanol under hydrogen borrowing conditions using a well-defined manganese PN3P complex as a pre-catalyst was, for the first time, achieved. The reactions typically proceed at 120 °C for 20 h with 3 mol% pre-catalyst loading and in the presence of NaOtBu (50 mol%) as base. The scope of the reaction was extended to the α-methylation of esters.
- Bruneau-Voisine, Antoine,Pallova, Lenka,Bastin, Stéphanie,César, Vincent,Sortais, Jean-Baptiste
-
supporting information
p. 314 - 317
(2019/01/09)
-
- Synthesis and in vitro antitumor and antimicrobial activity of some 2,3-diaryl-7-methyl-4,5,6,7-tetrahydroindazole and 3,3a,4,5,6,7-hexahydroindazole derivatives
-
The synthesis of a series of 2,3-diaryl-7-methyl-4,5,6,7-tetrahydroindazole and 3,3a,4,5,6,7-hexahydroindazole derivatives substituted with various biologically-active function groups with anticipated chemotherapeutic activity is described. 4-(7-methyl-3-aryl-3,3a,4,5,6,7-hexahydro-indazol-2-yl)benzenesulfonamides 2a-c, which were employed as key intermediates in this study, were synthesized by cyclocondensation of 6-arylidene-2-methylcyclohexanones 1a-c with 4-hydrazinobenzenesulfonamide hydrochloride. A detailed discussion of the reactions utilized in the preparation of the intermediate and target compounds is reported, and the structures of the newly synthesized compounds were substantiated with IR, 1H and 13C NMR spectral data and elementary microanalyses. Twenty of the newly synthesized compounds were selected by National Cancer Institute (NCI), Maryland, USA, to be evaluated for their antitumor activity and the results revealed that six compounds 3c, 4d,e, 5a,d and 8c exhibited broad spectrum of antitumor activity against most of the tested tumor cell lines. In addition, the in vitro antibacterial and antifungal activities of a number of the target compounds were also tested using the Agar-diffusion method. Some of these compounds have shown significant antibacterial and mild to moderate antifungal activities.
- Faidallah, Hassan M.,Khan, Khalid A.,Rostom, Sherif A.F.,Asiri, Abdullah M.
-
p. 495 - 508
(2015/02/19)
-
- Platinum-catalyzed cyclization/[1,2]-alkyl migration/allyl shift/cyclization cascade of epoxy alkynyl allyl ethers: A step-economical route to spirobenzo[h]chromanones
-
In tandem: A PtI4-catalyzed tandem reaction of epoxy alkynyl allyl ethers involving a cyclization, [1,2]-alkyl migration, O→C allyl shift, aromatic cyclization sequence has been achieved to synthesize spirobenzo[h]chromanones. The reaction simultaneously forms two adjacent stereocenters, one of which is a quaternary carbon atom (see scheme). Copyright
- Yang, Yan-Fang,Shu, Xing-Zhong,Luo, Jian-Yi,Ali, Shaukat,Liang, Yong-Min
-
supporting information; scheme or table
p. 8600 - 8604
(2012/09/07)
-
- Structural requirements of (E)-6-benzylidene-4a-methyl-4,4a,5,6,7,8- hexahydronaphthalen-2(3H)-one derivatives as novel melanogenesis inhibitors
-
Chalcone type compound 1a ((E)-6′-benzylidene-4a′-methyl- 4′,4a′,7′,8′-tetrahydro-3′H-spiro[[1,3] dithiolane-2,2′-naphthalen]-5′(6′H)-one) was discovered as an potent inhibitor in melanogenesis. To define its structure-activity relationship, a series of a
- Thanigaimalai, Pillaiyar,Lee, Ki-Cheul,Sharma, Vinay K.,Rao, Eeda Vekateswara,Roh, Eunmiri,Kim, Youngsoo,Jung, Sang-Hun
-
supporting information; experimental part
p. 1922 - 1925
(2011/04/24)
-
- Synthesis of 5-aryl-1-methyl-1,2,3,4-tetrahydrobenzo[a]phenanthridines
-
5-Aryl-1-methyl-1,2,3,4-tetrahydrobenzo[a]phenanthridines were synthesized by cascade heterocyclization of the corresponding substituted benzaldehydes with 2-methylcyclohexanone and naphthalen-2-amine in a polar solvent in the presence of hydrochloric acid.
- Kozlov,Basalaeva
-
experimental part
p. 587 - 590
(2009/09/06)
-
- Ring expansion/homologation-aldehyde condensation cascade using tert-trihalomethylcarbinols
-
Treatment of cyclic tert-trihalomethylcarbinols with CrCl2 in THF/HMPA in the presence of aryl or aliphatic aldehydes initiates a cascade sequence of one carbon ring expansion-olefination affording conjugated exocyclic ketones. Acyclic tert-trihalomethylcarbinols undergo a comparable cascade of one carbon homologation-olefination.
- Falck,He, Anyu,Manmohan Reddy,Kundu, Abhijit,Barma, Deb K.,Bandyopadhyay,Kamila, Sukanta,Akella, Radha,Bejot, Romain,Mioskowski, Charles
-
p. 4645 - 4647
(2007/10/03)
-
- The synthesis and fungicidal activity of 2-substituted 1-azol-1-ylmethyl-6-arylidenecyclohexanols
-
A number of substituted 2,2-dimethyl-6-arylidene-1-triazol-lylmethylcyclohexanols and 2,2-dimethyl-6-arylidene-1-imidazol-1-ylmethylcyclohexanols were prepared from 2-methylcyclohexanone in four steps: Claisen-Schmidt condensation with substituted benzald
- Popkov,Kovalenko,Bobylev,Molchanov,Krimer,Tashchi,Putsykin
-
p. 125 - 129
(2007/10/03)
-
- A Regioselective and Stereospecific Synthesis of Allylsilanes from Secondary Allylic Alcohol Derivatives
-
Primary and secondary allylic acetates and benzoates react with the dimethyl(phenyl)silyl-cuprate reagent to give allylsilanes, provided that the THF in which the cuprate is prepared is diluted with ether before addition of the allylic ester.The reaction is reasonably regioselective in some cases: (i) when the allylic system is more-substituted at one end than the other, as in the reactions 4->5 and 9->10; (ii) when the steric hindrance at one end is neopentyl-like, as in the reactions 15->16; and (iii) when the disubstituted double bond has the Z configuration, as in th e reactions Z-19->E-21 or, better, because the silyl group is becoming attached to the less-sterically hindered end of the allylic system, Z-20->E-22.The regioselectivity is better if a phenyl carbamate is used in place of the ester, and a three-step protocol assembling the mixed cuprate on the leaving group is used, as in the reactions 23->24 and E- or Z-29->E-21, or, best of all, because the silyl group is again becoming attached to the less-sterically hindered end of the allylic system, E- or Z-30->E-22.This sequence works well to move the silyl group onto the more substituted end of an allyl system, but only when the move is from a secondary allylic carbamate to a tertiary allylsilane, as in the reaction 38->39.Allyl(trimethyl)silanes can be made using alkyl- or aryl-cuprates on trimethylsilyl-containing allylic esters and carbamates, as in the reactions 40->41, and 43->44.The reaction of the silyl-cuprate with allylic esters and the three-step sequence with the allylic carbamates are stereochemically complementary, the former being stereospecifically anti and the latter stereospecifically syn.Homochiral allylsilanes can be ma de by these methods with high levels of stereospecificity, as shown by the synthesis of the allylsilanes 54, 58 and 59.
- Fleming, Ian,Higgins, Dick,Lawrence, Nicholas J.,Thomas, Andrew P.
-
p. 3331 - 3350
(2007/10/02)
-
- The Reaction of 2-Substituted Cycloalkanones with Aldehydes under Acidic Conditions
-
The title reaction proceeded with either ring enlargement or bicyclic compound formation, as well as the aldol reaction, depending upon the types of the reactants and reaction conditions.
- Sato, Tadashi,Hayase, Kengo
-
p. 3384 - 3389
(2007/10/02)
-
- Addition of 4-Hydroxycoumarin to &α,&β-Unsaturated Carbonyl Derivatives and Mannich Base Methiodides Derived from Cyclic Ketones
-
Five new 4-hydroxycoumarins incorporating a cyclic ketone have been synthesized, their structures established by PMR, IR and UV spectral data, and screened for their anticoagulant activity.
- Khanna, Vijay,Paraskar, Sunil R.,Ladwa, P. H.,Bhide, M. B.
-
p. 102 - 105
(2007/10/02)
-
- CATALYSE HETEROGENE PAR DES SELS ET SANS SOLVANT. III. SYNTHESE DE COMPOSES CARBONYLES α,β INSATURES A PARTIR D'ETHERS D'ENOLS SILYLES
-
The reactions of silyl enol ethers with carbonyl compounds are activated by heterogeneous catalysis.Caesium fluoride is the best catalyst.Unsaturated ketones are directly obtained by condensation reactions of silyl enol ethers with aldehydes and ketones. 1,4 Addition with α,β-unsaturated carbonyl compounds gives 1,5 dicarbonyl products.This method is very convenient and the compounds obtained can easily be separated.We assume that the role of the salt in these reactions is to activate the silicon atom by anionic coordination to form a pentacoordinated silicon intermediate.
- Boyer, J.,Corriu, R. J. P.,Perz, R.,Reye, C.
-
p. 157 - 166
(2007/10/02)
-