- Product-oriented chemical surface modification of a levansucrase (SacB): Via an ene-type reaction
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Carbohydrate processing enzymes are sophisticated tools of living systems that have evolved to execute specific reactions on sugars. Here we present for the first time the site-selective chemical modification of exposed tyrosine residues in SacB, a levansucrase from Bacillus megaterium (Bm-LS) for enzyme engineering purposes via an ene-type reaction. Bm-LS is unable to sustain the synthesis of high molecular weight (HMW) levan (a fructose polymer) due to protein-oligosaccharide dissociation events occurring at an early stage during polymer elongation. We switched the catalyst from levan-like oligosaccharide synthesis to the efficient production of a HMW fructan polymer through the covalent addition of a flexible chemical side-chain that fluctuates over the central binding cavity of the enzyme preventing premature oligosaccharide disengagement.
- Ortiz-Soto, Maria Elena,Ertl, Julia,Mut, Jürgen,Adelmann, Juliane,Le, Thien Anh,Shan, Junwen,Te?mar, J?rg,Schlosser, Andreas,Engels, Bernd,Seibel, Jürgen
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Read Online
- Crystal growth, structure, and polymorphic behavior of an ionic liquid: Phthalate derivative of N -Butyl, N -methylimidazolium Hexafluorophosphate
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After the multistep synthesis of an original imidazolium hexafluorophosphate ionic liquid, [pbmim][PF6], two polymorphic forms were isolated from methanolic solution and characterized by XRPD, DSC, and Raman spectroscopy. Stable Form A (mp 90.3 °C) was obtained by conventional crystallization at a moderate cooling rate (10 K/min) was applied. Structural analyses carried out by using single-crystal (Form A) and powder (Form B) X-ray diffraction revealed a rotational disorder of anionic octahedrons and, more interestingly, large conformational differences between cationic moieties caused by their molecular flexibility. Crystal growth of [pbmim][PF6] (Form A) in methanol often leads to numerous crystal defects and revealed that most of them consist of liquid inclusions. The supersaturation ratio (β) appeared to be the predominant factor influencing the crystal growth behavior under isothermal and stagnant conditions. At low β values, a morphological transition from rod-shaped crystals to platelets was observed, presumably caused by a change in the growth mechanism of specific faces. Using high β values promotes either the formation of microscopic (5 μm) liquid inclusions that become easily detectable upon heating or the appearance of macroscopic inclusions with an hourglass shape.
- Brandel, Clement,Gbabode, Gabin,Cartigny, Yohann,Martin, Claudette,Gouhier, Geraldine,Petit, Samuel,Coquerel, Gerard
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Read Online
- Structural essentials of xenoestrogen dialkyl phthalates to bind to the estrogen receptors
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Xenoestrogen dialkyl phthalates, C6H4(COOCnHm)2, lack the phenolic hydroxyl group that is an essential structural component of the steroid A ring of 17β-estradiol. In order to examine whether dialkyl phthalates imitate the steroid structure, we have synthesized a series of 4-hydroxyl derivatives of dialkyl phthalates. The compounds were examined for their ability to displace [3H]17β-estradiol from the recombinant human estrogen receptor, which was expressed on Sf9 cells using the vaculovirus expression system. Dialkyl 4-hydroxyl phthalates were found to exhibit several-fold higher binding affinities compared to phthalates without the 4-hydroxyl group. From the analyses of receptor binding modes of dialkyl phthalates with and without the 4-hydroxyl group, it was deduced that the phthalic benzene ring mimics the steroid A ring. A biphasic binding curve observed for dicyclohexyl phthalate was also depicted by its 4-hydroxyl derivative, but it increased binding affinity only at the high affinity binding site. These data suggest that the phthalate benzene moiety recognizes the core of the estrogen receptor binding site and the hydrophobic interaction of the dialkyl moiety substantiates the binding characteristics of the phthalates. The present data indicate that even chemicals with slight structural analogy and weak receptor affinity can perturb the endocrine system when administered in high concentrations.
- Asai, Daisuke,Tahara, Yoshiko,Nakai, Makoto,Yakabe, Yoshikuni,Takatsuki, Mineo,Nose, Takeru,Shinmyozu, Teruo,Shimohigashi, Yasuyuki
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Read Online
- BIFUNCTIONAL COMPOUNDS FOR THE TREATMENT OF CANCER
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The invention provides bifunctional compounds of formula (I) or a pharmaceutically acceptable salt thereof. Formula (I). The compounds cause the degradation of SMARCA2 via the targeted ubiquination of SMARCA2 protein and subsequent proteasomal degradation and are thus useful for the treatment of cancer. The targeting ligand is of formula (TL).
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Page/Page column 57; 87
(2021/05/07)
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- Iron-catalyzed arene C-H hydroxylation
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The sustainable, undirected, and selective catalytic hydroxylation of arenes remains an ongoing research challenge because of the relative inertness of aryl carbon-hydrogen bonds, the higher reactivity of the phenolic products leading to over-oxidized by-products, and the frequently insufficient regioselectivity. We report that iron coordinated by a bioinspired L-cystine-derived ligand can catalyze undirected arene carbon-hydrogen hydroxylation with hydrogen peroxide as the terminal oxidant. The reaction is distinguished by its broad substrate scope, excellent selectivity, and good yields, and it showcases compatibility with oxidation-sensitive functional groups, such as alcohols, polyphenols, aldehydes, and even a boronic acid. This method is well suited for the synthesis of polyphenols through multiple carbon-hydrogen hydroxylations, as well as the late-stage functionalization of natural products and drug molecules.
- Cheng, Lu,Wang, Huihui,Cai, Hengrui,Zhang, Jie,Gong, Xu,Han, Wei
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- Method for promoting iron-catalyzed oxidation of aromatic compound carbon - hydrogen bond to synthesize phenol by ligand
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The method comprises the following steps: iron is used as - a catalyst metal; a sulfur-containing amino acid or cystine-derived dipeptide is a ligand; and under the common action of hydrogen peroxide as an oxidizing agent, an aromatic compound is synthesized to prepare a phenol. Under the action of an acid as an accelerant and hydrogen peroxide as an oxidizing agent, the aryl carbon - hydrogen bond is directly hydroxylated to form a phenolic compound, and the method for preparing the phenol by the catalytic oxidation reaction has a plurality of advantages. The reaction raw materials, the oxidant and the promoter are wide in source, low in price, environment-friendly and good in stability. The aromatic compound carbon - hydrogen bonds directly participate in the reaction to react in one step to form phenol. The reaction condition is mild, the functional group compatibility and the application range are wide. The reaction selectivity is good; under the optimized reaction conditions, the target product separation yield can reach 85%.
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Paragraph 0108-0109; 0129
(2021/09/21)
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- NOVEL BROMINATED FURANONE DERIVATIVE, METHOD FOR PREPARING SAME, AND PHARMACEUTICAL COMPOSITION CONTAINING SAME AS ACTIVE INGREDIENT
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The present invention relates to a novel brominated furanone derivative, a method for preparing the same, and a pharmaceutical composition containing the same as an active ingredient, wherein the novel brominated furanone derivative or a pharmaceutically acceptable 5 salt thereof according to the present invention exhibits a quorum sensing inhibitory activity of bacteria and also can effectively inhibit the formation of biofilm of bacteria, and thus can be used as a pharmaceutical composition containing the same as an active ingredient, thereby having an effect of being useful, 10 for example, for periodontal diseases such as gingivitis and periodontitis, oral diseases, and the like.
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Paragraph 0192-0194; 0205-0207; 0219-0221; 0232-0235
(2019/11/22)
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- Automated on-line monitoring of the TiO2-based photocatalytic degradation of dimethyl phthalate and diethyl phthalate
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A fully automated on-line system for monitoring the TiO2-based photocatalytic degradation of dimethyl phthalate (DMP) and diethyl phthalate (DEP) using sequential injection analysis (SIA) coupled to liquid chromatography (LC) with UV detection was proposed. The effects of the type of catalyst (sol-gel, Degussa P25 and Hombikat), the amount of catalyst (0.5, 1.0 and 1.5 g L-1), and the solution pH (4, 7 and 10) were evaluated through a three-level fractional factorial design (FFD) to verify the influence of the factors on the response variable (degradation efficiency, %). As a result of FFD evaluation, the main factor that influences the process is the type of catalyst. Degradation percentages close to 100% under UV-vis radiation were reached using the two commercial TiO2 materials, which present mixed phases (anatase/rutile), Degussa P25 (82%/18%) and Hombikat (76%/24%). 60% degradation was obtained using the laboratory-made pure anatase crystalline TiO2 phase. The pH and amount of catalyst showed minimum significant effect on the degradation efficiencies of DMP and DEP. Greater degradation efficiency was achieved using Degussa P25 at pH 10 with 1.5 g L-1 catalyst dosage. Under these conditions, complete degradation and 92% mineralization were achieved after 300 min of reaction. Additionally, a drastic decrease in the concentration of BOD5 and COD was observed, which results in significant enhancement of their biodegradability obtaining a BOD5/COD index of 0.66 after the photocatalytic treatment. The main intermediate products found were dimethyl 4-hydroxyphthalate, 4-hydroxy-diethyl phthalate, phthalic acid and phthalic anhydride indicating that the photocatalytic degradation pathway involved the hydrolysis reaction of the aliphatic chain and hydroxylation of the aromatic ring, obtaining products with lower toxicity than the initial molecules.
- Salazar-Beltrán, Daniel,Hinojosa-Reyes, Laura,Maya-Alejandro, Fernando,Turnes-Palomino, Gemma,Palomino-Cabello, Carlos,Hernández-Ramírez, Aracely,Guzmán-Mar, Jorge Luis
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p. 863 - 870
(2019/04/17)
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- New bicyclic brominated furanones as potent autoinducer-2 quorum-sensing inhibitors against bacterial biofilm formation
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Bacterial behaviors such as virulence factor secretion and biofilm formation are critical for survival, and are effectively regulated through quorum sensing, a mechanism of intra- and interspecies communication in response to changes in cell density and species complexity. Many bacterial species colonize host tissues and form a defensive structure called a biofilm, which can be the basis of inflammatory diseases. Periodontitis, a chronic inflammatory disease affecting the periodontium, is caused by subgingival biofilms related to periodontopathogens. In particular, Fusobacterium nucleatum is a major co-aggregation bridge organism in the formation and growth of subgingival biofilms, linking the early and late colonizers in periodontal biofilms. According to our previous study, the intergeneric quorum-sensing signal molecule autoinducer-2 (AI-2) of F. nucleatum plays a key role in intra- and interspecies interactions of periodontopathogens, and may be a good target for periodontal biofilm inhibition. Recently, brominated furanones produced by the macroalga Delisea pulchra were shown to inhibit biofilm formation via AI-2, and have been investigated toward the goal of increasing the inhibition effect. In this study, we describe the synthesis of new bromofuranone analogs, i.e., 3-(dibromomethylene)isobenzofuran-1(3H)-one derivatives, and demonstrate their inhibitory activities against biofilm formation by periodontopathogens, including F. nucleatum, Porphyromonas gingivalis, and Tannerella forsythia.
- Park, Ji Su,Ryu, Eun-Ju,Li, Linzi,Choi, Bong-Kyu,Kim, B. Moon
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- NOVEL PRODRUGS OF DITHIOL MUCOLYTIC AGENTS
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Provided are mucolytic compounds that are more effective, and/or absorbed less rapidly from mucosal surfaces, and/or are better tolerated as compared to N-acetylcysteine (NAC) and DTT. The compounds are represented by compounds of Formula I which embrace structures (la)-(Ib), where the structural variables are as defined herein.
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Page/Page column 74
(2016/11/17)
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- Of tetracyclic Anaplastic lymphoma kinase inhibitors (by machine translation)
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The invention belongs to the field of medical technology, in particular to general formula (I) as shown in of tetracyclic Anaplastic lymphoma kinase inhibitor, its pharmaceutically acceptable salt or a stereoisomer thereof, wherein R 1, R 2, R 3, R 4, R 5 and A link like defined in the specification. The invention also relates to methods of preparing such compounds, pharmaceutical preparations comprising these compounds and pharmaceutical composition, the compound and, its pharmaceutically acceptable salts or stereoisomers thereof, in the preparation of the treatment and/or prevention of Anaplastic lymphoma kinase-mediated cancer diseases related to the application of the medicament. (by machine translation)
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Paragraph 0221; 0222; 0223
(2016/10/08)
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- Divergent Reactivity of Thioalkynes in Lewis Acid Catalyzed Annulations with Donor–Acceptor Cyclopropanes
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Efficient methods for the convergent synthesis of (poly)cyclic scaffolds are urgently needed in synthetic and medicinal chemistry. Herein, we describe new annulation reactions of thioalkynes with phthalimide-substituted donor–acceptor cyclopropanes, which gave access to highly substituted cyclopentenes and polycyclic ring systems. With silyl-thioalkynes, the Lewis acid catalyzed [3+2] annulation reaction with donor–acceptor cyclopropanes took place to afford 1-thio-cyclopenten-3-amines. On the other hand, an unprecedented polycyclic compound was formed with alkyl-thioalkynes through a reaction pathway directly involving the phthalimide group. The two transformations proceeded in good yields and tolerated a large variety of functional groups.
- Racine, Sophie,Hegedüs, Bence,Scopelliti, Rosario,Waser, Jér?me
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supporting information
p. 11997 - 12001
(2016/08/16)
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- DITHIOL MUCOLYTIC AGENTS
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Provided are dithiol mucolytic agents. These agents increase the liquefaction of mucus in a patient with excessive mucus or mucus with increased viscoelastic, cohesive, or adhesive properties. Also provided are a variety of methods of treatment using these inventive mucolytic agents.
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Paragraph 0270; 0271; 0387; 0388
(2015/03/04)
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- PROCESSES FOR PREPARING ISOINDOLINE-1,3-DIONE COMPOUNDS
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Provided herein are processes for preparing an isoindoline- 1.3-dione compound, or an enantiomer or a mixture of enantiomers thereof; or a pharmaceutically acceptable salt, solvate, hydrate, or polymorph thereof.
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Paragraph 00175; 00176
(2014/02/16)
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- Dynamic kinetic asymmetric [3 + 2] annulation reactions of aminocyclopropanes
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We report the first example of a dynamic kinetic asymmetric [3 + 2] annulation reaction of aminocyclopropanes with both enol ethers and aldehydes. Using a Cu catalyst and a commercially available bisoxazoline ligand, cyclopentyl- and tetrahydrofurylamines were obtained in 69-99% yield and up to a 98:2 enantiomeric ratio using the same reaction conditions. The method gives access to important enantio-enriched nitrogen building blocks for the synthesis of bioactive compounds.
- De Nanteuil, Florian,Serrano, Eloisa,Perrotta, Daniele,Waser, Jerome
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supporting information
p. 6239 - 6242
(2014/05/20)
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- 3-Heterocycle-phenyl N-alkylcarbamates as FAAH inhibitors: Design, synthesis and 3D-QSAR studies
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Carbamates are a well-established class of fatty acid amide hydrolase (FAAH) inhibitors. Here we describe the synthesis of meta-substituted phenolic N-alkyl/aryl carbamates and their in vitro FAAH inhibitory activities. The most potent compound, 3-(oxazol-2yl)phenyl cyclohexylcarbamate (2a), inhibited FAAH with a sub-nanomolar IC50 value (IC50=0.74 nM). Additionally, we developed and validated three-dimensional quantitative structure-activity relationships (QSAR) models of FAAH inhibition combining the newly disclosed carbamates with our previously published inhibitors to give a total set of 99 compounds. Prior to 3D-QSAR modeling, the degree of correlation between FAAH inhibition and in silico reactivity was also established. Both 3D-QSAR methods used, CoMSIA and GRID/GOLPE, produced statistically significant models with coefficient of correlation for external prediction (R2 PRED) values of 0.732 and 0.760, respectively. These models could be of high value in further FAAH inhibitor design.
- Kaesnaenen, Heikki,Myllymaeki, Mikko J.,Minkkilae, Anna,Kataja, Antti O.,Saario, Susanna M.,Nevalainen, Tapio,Koskinen, Ari M. P.,Poso, Antti
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experimental part
p. 213 - 231
(2010/11/18)
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- NOVEL GLUCOKINASE ACTIVATORS AND METHODS OF USING SAME
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Compounds are provided which are glucokinase activators and thus are useful in treating diabetes and related diseases and have the structure wherein in the ring represents one or two double bonds; R1 is aryl or heteroaryl; R2 is halogen, cycloalkyl, heterocyclyl, aryl, or heteroaryl; R5 is as defined herein; Z is O, S, S(O), S(O)2, or NR5a; X is S, O, N, NR3, or CR3; Y is NCR4 or N4; R3, R4, and R5 are as defined herein; R8 is aryl or heteroaryl; R6 and R7 are independently H, halogen, or alkyl; m is 0 or 1; and n is 0 to 3, or a pharmaceutically acceptable salt thereof. A method for treating diabetes and related diseases employing the above compounds is also provided.
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(2008/06/13)
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- BENZOQUINAZOLINE DERIVATIVES AND THEIR USE IN TREATING BONE DISORDERS
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A compound of formula (I) or a pharmaceutically acceptable salt or prodrug ester thereof, wherein the groups R2, R3, R4, Q, X and Y are as defined in the specification, is useful in the treatment of bone conditions related to increased calcium depletion or resorption.
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Page/Page column 97-98
(2008/06/13)
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- Vitamin D analogues
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The invention concerns novel bi-aromatic compounds having the formula: which are analogs of vitamin D, the process of preparing them, as well as their use in pharmaceutical compositions in human or veterinary medicine, particularly in dermatology, cancer treatment, treatment of auto-immune diseases, and in organ or tissue transplants. Cosmetic compositions and methods of use are also included.
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(2010/02/05)
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- Vitamin D analogues
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The invention relates to novel bicyclic compounds having the general formula (I): as well as to a method for preparing them and to their use in pharmaceutical compositions intended for use in human or veterinary medicine (in dermatology, in carcinology and in the field of autoimmune diseases and that of organ or tissue transplants in particular), or alternatively in cosmetic compositions.
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(2010/02/05)
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- Convenient syntheses of fluorous phenols of the formula triarylphosphites
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The aldehydic benzyl ethers PhCH2OC6H4CHO (2; a/b = paralmeta series) are readily available from the corresponding phenols and react with Wittig reagents derived from [Ph3PCH2CH2Rf8]+- (Rf8 = (CF2)7CF3) to give PhCH2OC6H4CH=CHCH2Rf8 (86-93%, Z major). Reactions with H2 over Pd/C give the fluorous phenols HOC6H4(CH2)3Rf8 (4a,b; 87-91%). Condensations with PCl3 and NEt3 (3.0:1:0:3.3 mol ratio) give the flourous phosphites P[OC6H4(CH2)3Rf8] 3 (5a,b; 92-94%), but traces of 4a,b are difficult to remove. The phthalate-based benzyl ethers PhCH2OC6H3COOR 2 (7; c/d = 3,5/3,4 -OC6H3-3,n-(R)2 series) are easily accessed and reduced with LiAlH4 to the diols PhCH2OC6H3(CH2OH)2 (8c,d; 89-90%). Diol 8c and the Dess-Martin periodinane react to give the dialdehyde PhCH2OC6H3(CHO)2 (9C; 95%). This is elaborated by a sequence analogous to 2 → 4 → 5 to the flourous phenol HOC6H3((CH2)3Rf8) 2 (11c; 97%/96%, two steps) and phosphite P[OC6H3((CH2)3Rf8) 2]3 (12C, 92%), from which traces of 11c are difficult to remove. Diol 8d can be similarly elaborated to 11d, but the dialdehyde 9d is labile and combined yield of the Dess-Martin/Wittig steps is 32%. The CF3C6F11/ toluene partition coefficients of 11c,d, and 12c (two pony tails; 70:30,72:28, 92:8) are much higher than those of 4a and b (one pony tail; 12:88, 14:86).
- Le Stang, Sylvie,Meier, Ralf,Rocaboy, Christian,Gladysz
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p. 141 - 149
(2007/10/03)
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- A new class of glycogen phosphorylase inhibitors
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A new class of diacid analogues that binds at the AMP site not only are very potent but have ～10-fold selectivity in liver versus muscle glycogen phosphorylase (GP) in the in vitro assay. The synthesis, structure, and in vitro and in vivo biological evaluation of these liver selective glycogen phosphorylase inhibitors are discussed.
- Lu, Zhijian,Bohn, Joann,Bergeron, Raynald,Deng, Qiaolin,Ellsworth, Kenneth P.,Geissler, Wayne M.,Harris, Georgianna,McCann, Peggy E.,McKeever, Brian,Myers, Robert W.,Saperstein, Richard,Willoughby, Christopher A.,Yao, Jun,Chapman, Kevin
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p. 4125 - 4128
(2007/10/03)
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- Aromatic compounds
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Disclosed are compounds of formula I wherein A, R1, R2, R3, R4and R5are described in the specification, pharmaceutical formulations comprising these compounds, the use of these compounds are medicaments, the use of these medicaments in the treatment of and/or prevention of diabetes, especially non-insulin dependent diabetes (NIDDM or Type 2 diabetes), as well as methods for treating diabetes comprising administration of these compounds.
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- Site selectivity of the diels-alder reactions of 3-[1-(tert-butyldimethylsilyloxy)vin-1-yl]furan and 3-(propen-2-yl)furan. Synthesis of 4-substituted benzofurans
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The Diels-Alder reaction of 3-vinylfurans 5 and 27 with DMAD, N-phenylmaleimide, and dimethyl maleate afforded products derived both from addition to the furan ring diene system (intraannular addition) and to the furan 2,3-double bond 3-vinyl group diene system (extraannular addition). For example, compounds 6 and 7 were obtained from 5 and DMAD. In contrast, dienophiles containing a phenylsulfinyl group, such as 19-21, gave products derived exclusively from the extraannular reaction mode. These products are useful precursors of 4-substituted benzofurans, especially 4-hydroxybenzofurans.
- Benítez, Aida,Herrera, F. Ruth,Romero, Margarita,Talamás, Francisco X.,Muchowski, Joseph M.
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p. 1487 - 1489
(2007/10/03)
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- Salicylic acid derivatives
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The heat-sensitive recording material disclosed comprises a colorless or pale colored dyestuff precursor, one or more salicylic acid derivative of the formula (1) or metal salt of the derivative and an aliphatic amide compound having 18?60 carbon atoms in molecular structure, and is excellent in thermal response and preservation stability of white portions and images. STR1 wherein X1 and X2 are a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an aralkyl group or an aryl group, Y1 and Y2 are an oxygen atom or a sulfur atom, R1 is a hydrogen atom, an alkyl group, an aralkyl group or an aryl group, and R2 is an alkyl group, an alkenyl group, an aralkyl group or an aryl group.
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- Synthetic routes to ninhydrins. Preparation of ninhydrin, 5-methoxyninhydrin, and 5-(methylthio)ninhydrin
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Two syntheses of 5-methoxyninhydrin (2,2-dihydroxy-5-methoxy-1,3-indanedione) are described. One method employs a novel and efficient two step route, which begins with commercially available 6-methoxy-1-indanone. The application of this strategy for the preparation of a new ninhydrin derivative, 5-(methylthio)ninhydrin, and ninhydrin is also presented.
- Heffner,Joullie
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p. 2231 - 2256
(2007/10/02)
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- A synthesis of two novel benzo[f]ninhydrin analogs: 6-methoxybenzo[f]ninhydrin and thieno[f]ninhydrin
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Improved methodology for the synthesis of benzo[f]ninhydrin (1) is described. The generality of this approach is illustrated with the synthesis of two novel analogs, 6-methoxybenzo[f]ninhydrin (3) and thieno[f]ninhydrin (4).
- Heffner,Joullie
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p. 1055 - 1069
(2007/10/02)
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- Photochemical Additions of Alkenes to Phthalimides. Mechanistic Investigations on the Stereochemistry of Alkene Additions and the Effect of Aryl Substituents on the Regiochemistry of Alkene Additions
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The mechanism of the photochemical addition of alkenes to phthalimides was investigated by determining the stereochemistry of the addition and the effect of aryl substituents on the regiochemistry.Intra- and intermolecular examples were examined.The stereochemistry of the addition of cis- and trans-2-butene to N-methylphthalimide to give 2,3,4-trimethyl-2-benzazepine-1,5-dione was studied.It was found that both alkenes added stereospecifically, each giving the corresponding cis- or trans-2,3,4-trimethyl-2-benzazepine-1,5-dione with >95percent stereospecificity.The mechanistic implication of this result is either that the photochemical addition is a concerted (2 + 2) addition or that any intermediate biradical closes faster than rotation around the C-C bond which would result in loss of stereochemistry.A second approach to this problem employed the directive effects of aryl substituents.The proposed biradical intermediate is similar in structure to the phthalimide radical anion.The directive effects of aryl substituents have been experimentally determined in this system and are consistent with theoretical predictions.Theoretical predictions for aryl-substituent directive effects in the alternative concerted (2 + 2) process are opposite to those for the biradical case, which predicts that donors will direct meta and acceptors para.Irradiation of 4-methoxy- and 4-carbomethoxy-N-methylphthalimide in the presence of 1-hexene afforded the benzazepinedione addition products that resulted from addition to the para and meta C(O)-N bonds, respectively.These results are entirely consistent with a concerted process.
- Mazzocchi, P. H.,Wilson, P.,Khachik, F.,Klingler, L.,Minamikawa, S.
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p. 2981 - 2989
(2007/10/02)
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