31357-82-1Relevant academic research and scientific papers
Efficient synthesis of 4- And 5-substituted 2-aminopyrimidines by coupling of β-Chlorovinyl Aldehydes and Guanidines
Komendantova, Anna S.,Komkov, Alexander V.,Volkova, Yulia A.,Zavarzin, Igor V.
supporting information, p. 4247 - 4254 (2018/08/24)
A general, practical, and simple synthesis of functionalized 2-aminopyrimidines starting from β-chlorovinyl aldehydes and amidines is reported. In the presence of potassium carbonate, various ketones have been efficiently transformed into the pyrimidine derivatives by a two-step sequence involving the Vilsmeier-Haack reaction followed by a condensation reaction with guanidines. The protocol is distinguished by operational simplicity, inexpensive reagents, and functional-group tolerance. In many cases, pure solid products can be obtained in high to excellent yields without using column chromatography. The synthetic value of the method was demonstrated by the efficient synthesis of steroidal pyrimidines and a precursor of the antitumor agents Imatinib and Mocetinostat.
A Straightforward Approach toward Multifunctionalized Pyridazines via Imination/Electrocyclization
Komkov, Alexander V.,Komendantova, Anna S.,Menchikov, Leonid G.,Chernoburova, Elena I.,Volkova, Yulia A.,Zavarzin, Igor V.
supporting information, p. 3734 - 3737 (2015/08/18)
A facile synthesis of functionalized 3-carbamide pyridazines starting from readily available chlorovinyl aldehydes and oxamic acid thiohydrazides via cascade imination/electrocyclization is reported. In the presence of p-toluenesulfuric acid, various ketones have been efficiently incorporated into the pyridazine derivatives through a two-step sequence involving a Vilsmeier-Haack reaction and imination. The synthetic value of this method has been demonstrated by efficient synthesis of steroidal pyridazines.
Synthesis of novel β-aryl-β-(methylthio)acroleins via Vilsmeier-Haack protocol as potential 1,3-dielectrophilic three-carbon building blocks
Byre Gowda,Charanraj,Pradeepa Kumara,Ramesh,Thomas,Sadashiva,Junjappa
, p. 4475 - 4479 (2014/08/05)
A new general route for the synthesis of novel β-aryl-β- (methylthio)acroleins, a class of stable potential 1,3-dielectrophilic synthons, has been reported. The overall protocol involves treatment of either β-chloroacroleins or their precursor iminium salts (generated in situ from the corresponding active methylene ketones under Vilsmeier-Haack reaction conditions) with S,S-dimethyldithiocarbonates (DDC)/aqueous KOH in either a one-pot or two-step process. The dimethyldithiocarbonate (DDC)/30% aqueous KOH has been shown to be an excellent source of methylthiolate anion.
A versatile methodology for the synthesis of α,β-unsaturated 3-iminophosphines
Shaffer, Andrew R.,Schmidt, Joseph A. R.
experimental part, p. 2662 - 2673 (2009/12/03)
Fourteen new αβ-unsaturated β-chloroimines were synthesized from commercially available ketones using the Vilsmeier-Haack reagent, followed by Schiff-base condensation. Each imine was subsequently converted to an αβ-unsaturated 3-iminophosphine through either late-metal-catalyzed phosphorus-carbon cross-coupling or through an addition-elimina-tion sequence. Depending on the substituents present on the vinyl group, the resultant phosphines were isolated as either E or Z diastereomers with successful isolation of predominately single diastereomers for all fourteen new phosphines investigated. Full synthetic and spectroscopic details, as well as several X-ray crystal structures of these new imines and phosphines, are reported in addition to X-ray crystal structures of related palladium complexes.
Stereochemical course of baker's yeast mediated reduction of the tri- and tetrasubstituted double bonds of substituted cinnamaldehydes
Fronza, Giovanni,Fuganti, Claudio,Serra, Stefano
experimental part, p. 6160 - 6171 (2010/03/24)
A comprehensive study of the stereochemical course of baker's yeast mediated reduction of substituted cinnamaldehydes is reported. Hydride addition to the β position of β-methylcinnamaldehydes preferentially afforded isomers of (3S)-3-phenylbutan-1-ol. The reduction of (E)-2,3-dimethyl- cinnamaldehyde (15) produced a mixture of (2S,3S)- and (2R,3S)-2-methyl-3- phenylbutan-1-ol (13 and 14), respectively, with 93 % ee. Conversely (Z)-2,3-dimethylcinnamal-dehyde (16) afforded, a mixture of 13 and 14 with 33 % ee. Accordingly, the reduction of trisubstituted β-methylcinnam-aldehydes 34 and 35 proceeded with the same stereochemical preference and with higher enantioselectivity to give (S) 3-phenylbutan-1-ol (37). In addition, deuterium, incorporation and 2H NMR studies demonstrated that the addition of the second hydrogen atom to the a position proceeded with very low stereochemical control and the overall process is formally a mixture of cis/trans hydrogen addition to the double bond. Alternatively, α-methylcinnamaldehyde is reduced to (S)-2-methyl-3-phenylpropan-1-ol (24) with preferential addition of the hydride to the opposite β face with good stereochemical control of the irons addition of hydrogen to the double bond. Wiley-VCH Verlag GmbH & Co. KGaA.
Synthesis and biological evaluation of guanylhydrazone coactivator binding inhibitors for the estrogen receptor
LaFrate, Andrew L.,Gunther, Jillian R.,Carlson, Kathryn E.,Katzenellenbogen, John A.
experimental part, p. 10075 - 10084 (2009/04/06)
Most patients with hormone-responsive breast cancer eventually develop resistance to traditional antiestrogens such as tamoxifen, and this has become a major obstacle in their treatment. We prepared and characterized the activity of a series of 16 guanylhydrazone small molecules that are designed to block estrogen receptor (ER) activity through a non-traditional mechanism, by directly interfering with coactivator binding to agonist-liganded ER. The inhibitory activity of these compounds was determined in cell-based transcription assays using ER-responsive reporter gene and mammalian two-hybrid assays. Several of the compounds gave IC50 values in the low micromolar range. Two secondary assays were used to confirm that these compounds were acting through the proposed non-traditional mode of estrogen inhibitory action and not as conventional antagonists at the ligand binding site.
Synthesis and stereochemistry of β-aryl-β-haloacroleins: Useful intermediates for the preparation of (Z) and (E)-2-en-4-ynecarbaldehydes and for the synthesis of rubrolides
Prim, Damien,Fuss, Alexia,Kirsch, Gilbert,Silva, Artur M. S.
, p. 1175 - 1180 (2007/10/03)
The synthesis of α-substituted β-aryl-β-haloacroleins by two different pathways is presented. The determination of their stereochemistry by NOE experiments is reported for the first time. Furthermore, we describe the preparation of 2-en-4-ynecarbaldehydes
On the regio and stereo selective formylations of acyclic alpha methylene ketones towards Vilsmeier Haack reagent
Chakraborty,Ray
, p. 1869 - 1876 (2007/10/02)
The regio and stereo selectivities of Vilsmeier Haack reaction of ketomethylene compounds have been predicted. The possible mechanistic pathway has also been proposed.
