- Synthesis of ω-phthalimidoalkylphosphonates
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Diethyl phthalimidoalkylphosphonates were synthesized by the reaction of diethyl bromoalkylphosphonates with N-(tert-butyldimethylsilyl)phthalimide in the presence of tetrabutylammonium fluoride.
- Chun,Park,Oh,Hong,Kim
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- Elucidating the Reaction Pathway of Decarboxylation-Assisted Olefination Catalyzed by a Mononuclear Non-Heme Iron Enzyme
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Installation of olefins into molecules is a key transformation in organic synthesis. The recently discovered decarboxylation-assisted olefination in the biosynthesis of rhabduscin by a mononuclear non-heme iron enzyme (P.IsnB) represents a novel approach in olefin construction. This method is commonly employed in natural product biosynthesis. Herein, we demonstrate that a ferryl intermediate is used for C-H activation at the benzylic position of the substrate. We further establish that P.IsnB reactivity can be switched from olefination to hydroxylation using electron-withdrawing groups appended on the phenyl moiety of the analogues. These experimental observations imply that a pathway involving an initial C-H activation followed by a benzylic carbocation species or by electron transfer coupled β-scission is likely utilized to complete C=C bond formation.
- Yu, Cheng-Ping,Tang, Yijie,Cha, Lide,Milikisiyants, Sergey,Smirnova, Tatyana I.,Smirnov, Alex I.,Guo, Yisong,Chang, Wei-Chen
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supporting information
p. 15190 - 15193
(2018/11/23)
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- New advances in the synthesis of tripyridinophane macrocycles suitable to enhance the luminescence of Ln(III) ions in aqueous solution
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A series of four new 18-membered hexaaza macrocyclic ligands bearing three endocyclic pyridine units and acetate or methylenephosphonate pendant arms has been prepared. The new synthetic procedure is based on the use of amine and diamine precursors incorporating masked carboxylate or phosphonate functions and on an efficient sodium template effect which controls the crucial macrocyclization step (yields of macrocyclization reactions: 62–88%). This procedure appears as a suitable alternative compared to the classical Richman-Atkins methodology generally used for the preparation of this class of macrocycles. As demonstrated with the EuIII and TbIII complexes derived from two ligands, these tripyridinophane chelators form luminescent and stable mononuclear LnIII complexes in aqueous solution at physiological pH. In such a medium, TbIII complexes exhibit a brightness of 1700 (λexc = 279 nm) and 3000 (λexc = 268 nm) M?1 cm?1.
- Leygue, Nadine,Perez e I?iguez De Heredia, Aritz,Galaup, Chantal,Benoist, Eric,Lamarque, Laurent,Picard, Claude
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p. 4272 - 4287
(2018/07/06)
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- THIENOPYRIMIDINE INHIBITORS OF FARNESYL AND/OR GERANYLGERANYL PYROPHOSPHATE SYNTHASE
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The present invention relates to novel compounds, compositions containing same and methods for inhibiting human farnesyl pyrophosphate synthase or for the treatment or prevention of disease conditions using said compounds;
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Page/Page column 39
(2014/06/11)
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- A novel and efficient route for the preparation of atorvastatin
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A novel and efficient synthetic method of atorvastatin was described. The key step of the synthesis was the construction of the olefin linkage between the chiral side chain and skeleton via a Horner-Wadsworth-Emmons reaction, resulting in the advanced intermediate of atorvastatin under hydrogenation of the olefin over Pd/C. This novel method is more useful for the practical synthesis of atorvastatin than its document reported methods.
- Gao, Jian,Guo, Yang Hui,Wang, Ya Ping,Wang, Xiang Jing,Xiang, Wen Sheng
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scheme or table
p. 1159 - 1162
(2012/01/16)
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- NOVEL PYRROLE DERIVATIVES AND THEIR SYNTHESIS
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The present invention relates to two novel pyrrole derivatives [3-Phenyl-4-(phenylcarbamoyl)-2-(4-fluorophenyl)-5-(1-methylethyl)-pyrrole-1-yl]methyl(diphenyl)phosphine oxide and Diethyl [3-Phenyl-4-(phenylcarbamoyl)-2-(4-fluorophenyl)-5-(1-methylethyl)-pyrrole-1-yl]methylphosphonate. These pyrrole derivatives can be used as intermediates for the synthesis of the anticholesterol drug atorvastatin.
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Page/Page column 4
(2011/11/06)
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- A SET OF GELDANAMYCIN DERIVATIVES AND THEIR PREPARATION METHODS
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A set of geldanamycin derivatives and their preparation methods. Pharmaceutical compositions comprising the said compounds as an active ingredient which are used as antivirus and antitumor agents. The said derivatives are used in the manufacture of heat shock protein 90(Hsp 90) inhibiting agents which have the utility as antivirus and antitumor agents.
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(2010/12/17)
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- Efficient synthesis routes for various phthalimido phosphor esters as antimicrobial agents in terms of structure-activity relationship
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A series of phthalimido phosphor derivatives α-amino-phosphonates, amidophosphonates, phosphonic acid diamides, and oxadiazaphospholes-were prepared by applying different types of phosphorus(III) reagents to 2-methoxy-1H-isoindole-1,3(2H)-dione and 2-anilino-1H-isoindole-1,3(2H)-dione. On the basis of bioassay results, some of the new phosphoryl imides could be considered as lead molecules to be modified in order to improve their antibiotic activity. Springer-Verlag 2010.
- Abdou, Wafaa Mahmoud,Khidre, Rizk E.
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experimental part
p. 219 - 228
(2010/08/05)
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- Synthesis and relaxometric studies of a dendrimer-based pH-responsive MRI contrast agent
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The design of effective pH responsive MRI contrast agents is a key goal in the development of new diagnostic methods for conditions such as kidney disease and cancer. A key factor determining the effectiveness of an agent is the difference between the rel
- Ali, M. Meser,Woods, Mark,Caravan, Peter,Opina, Ana C. L.,Spiller, Marga,Fettinger, James C.,Sherry, A. Dean
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body text
p. 7250 - 7258
(2009/09/06)
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- pH sensitive MRI contrast agents
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A composition and method is disclosed for providing a magnetic resonance imaging contrast agent that is sensitive to pH, the compound and salts thereof including, a tetraaza base having a spacer at each of the amide groups, and a proton exchange attached to each of the spacer molecules, wherein the proton exchange group groups mediate proton exchange with water molecules that are trapped within the tetraaza base molecule.
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(2008/06/13)
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- Phosphonate diester and phosphonamide synthesis. Reaction coordinate analysis by 31P NMR spectroscopy: Identification of pyrophosphonate anhydrides and highly reactive phosphonylammonium salts
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A series of phosphonochloridates was prepared from the corresponding phosphonate monoesters, and their reactions with alcohols, amines, and the bisnucleophile 4-aminobutan-1-ol have been investigated using 31P NMR spectroscopy. In the conversion of phosphonate monoesters to phosphonochloridates via the addition of thionyl chloride or oxalyl chloride, pyrophosphonate anhydrides were found to be formed readily as byproducts. The anhydrides reacted readily with alcohols, but more slowly than the corresponding phosphonochloridates, and only sluggishly, if at all, with amines. Therefore, when phosphonamides are prepared, anhydride formation must be suppressed. This is accomplished when the monoester is added to the chloridating agent. Unhindered phosphonochloridates reacted predominantly with the amino function of 4-aminobutan-1-ol to furnish the phosphonamidates, whereas a sterically hindered phosphonochloridate demonstrated a preference for O-coupling. This result indictes that the energy gained during P-O bond formation surmounts the kinetic barrier resulting from steric hindrance more effectively than formation of the weaker P-N bond. Importantly, treatment of the phosphonochloridates with tertiary amines prior to addition of the nucleophile resulted in the formation of hitherto unrecognized phosphonylating agents, which we formulated as phosphonyltrialkylammonium salts. The latter, unlike the anhydrides, are more reactive than the phosphonochloridates toward both alcohols and amines, affording improved yields of phosphonate esters and amides. These improved yields are not obtained when triethylamine is added simultaneously with the nucleophile merely to neutralize acid rather than as a deliberate step to generate the phosphonyltrialkylammonium salts. Use of these novel phosphonylating agents proceeded without concomitant racemization at stereogenic centers α to phosphorous. Interestingly, reaction of even an unhindered phosphonyltriethylammonium salt with 4-aminobutan-1-ol favored O-phosphonylation over N-phosphonylation by a factor of 8, demonstrating that both the charge transfer in the transition state and steric hindrance affect the propensity for P-O vis a vis P-N bond formation. In marked contrast, simultaneous addition of this bisnucleophile and triethylamine, like coupling in the absence of tertiary amine, afforded the phosphonate and phosphonamide in nearly equal amounts.
- Hirschmann, Ralph,Yager, Kraig M.,Taylor, Carol M.,Witherington, Jason,Sprengeler, Paul A.,Phillips, Barton W.,Moore, William,Smith III, Amos B.
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p. 8177 - 8190
(2007/10/03)
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- ORGANOPHOSPHORUS COMPOUNDS AS POTENTIAL FUNGICIDES. PART II. AMINOALKANE-, GUANIDINOALKANE-, AND THIOUREIDOALKANE-PHOSPHONIC ACIDS: PREPARATION, SPECTROSCOPY, AND FUNGICIDAL ACTIVITY
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A range of α-amino-, ω-amino-, α-guanidino-, and ω-guanidinoalkanephosphonic acids has been prepared for the purpose of studying their spectroscopic features and fungicidal activity.In addition, α-thioureido-octanephosphonic acid and thioureylene-1,1-bis(1-octanephosphonic acid) were isolated during the preparation of α-guanidino-octanephosphonic acid. 31P, 1H, and 13C nmr spectral data which were obtained for solutions of the amino- and guanidino-compounds in D2O or D2O/D2SO4, and for the thioureido compounds in DMSO-d6, are discussed together with previouslyreported data for the aminophosphonic types.FAB mass spectrometry generally gives strong pseudomolecular ions + for the zwitterionic amino- and guanidino-compounds with relatively simple fragmentations.Fungicidal activity of the α-aminophosphonic acids was found to be greater than for the ω-amino compounds, with maximum activity at a chain length of three carbon atoms when used as a seed dressing for the control of Drechslera spp.Moderately good activity was shown by the thioureido compounds against a number of fungal organisms in vitro but the guanidino-compounds exhibited low activity.Key words: Organophosphorus; fungicides; aminophosphonic acids; guanidinophosphonic acids; NMR spectroscopy; FAB mass spectroscopy.
- Cameron, David G.,Hudson, Harry R.,Pianka, Max
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- CONVERSION OF AMINO ACIDS AND DIPEPTIDES INTO THEIR PHOSPHONIC ANALOGS; Aminoalkylphosphonic acids and peptides II.
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Acylamino carboxylic acids were degradated by the Hunsdiecker-reaction; the bromo-derivatives were reacted with NaPO(OC2H5)2.Aminophosphonic acids were obtained by acidic hydrolysis, and half-blocked derivatives by the selective removal of masking substituents.Two phosphonopeptides were also prepared by this route.
- Oesapay, George,Szilagyi, Ildiko,Seres, Jenoe
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p. 2977 - 2984
(2007/10/02)
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- Tripeptides and methods for their production
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New tripeptides having the formula A-R1 -Ser(benzyl)-Tyr (benzyl)-R2 wherein A is t-butoxycarbonyl or cyclohexyl carbonyl, R1 is Trp, His(benzyl), Cys(benzyl) or Pro and R2 is lower alkoxy, hydrazino, amino, lower alkylamino, di(lower alkyl)amino, benzylamino, allylamino, (diethoxyphosphinyl)methylamino, 2-(diethoxyphosphinyl)ethylamino or 2-[[(phenylmethyl)amino]sulfonyl]ethylamino, methods for their production, and the use of said tripeptides as luteinizing hormone releasing factor antagonists.
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