bluuebunny/crossref_metadata_2025_split huggingface dataset:
Annual and spatial variation of intertidal benthic community zonation in a breakwater off the Rio de Janeiro coast, south-eastern Brazil
Authors: Masi Bruno Pereira , Macedo Isabela Maria , Zalmon Ilana Rosental 
Published: April 2009

The present study aims to evaluate the vertical distribution of intertidal benthic organisms in different periods of the year, relating them to tide, air temperature, height and wave periodicity in breakwaters off the northern Rio de Janeiro State, and to compare the zonation at two sites (Pier and Barra) with distinct hydrodynamics, due to different wave swell. Quadrats of 400 cm2 were sampled by a photoquadrat method. The upper limit of the marine organisms was higher at the Barra site (intertidal zone of 3.8 m) than at the Pier site (intertidal zone of 2.2 m). The littoral fringe assemblage did not show significant differences between sites, but a larger range of this fringe and the upper eulittoral band at Barra was quite evident. This site was mostly characterized by species of more exposed areas such as Chaetomorpha sp. and Perna perna in the upper and lower eulittoral bands, and by C. teedii and Ulva fasciata in the sublittoral fringe. A seasonal difference was identified in the air exposure degree at the Pier site, which was higher in October 2005 and February 2006. The air temperature and wave height and periodicity differed significantly among the four studied periods. The typical seasonal species were F. clenchi (July 2005 and October 2005), Gigartina domingensis (July 2005), Grateloupia sp. (October 2005) and Porphyra acanthophora (October 2005 and February 2006). The intermediate benthic band of the intertidal zone occupied a narrow zone, changing its spatial location according to the season of the year. The hypothesis of annual variation of the benthic community zonation according to the seasonal variability of tides, air temperatures and wave's height and periodicity was accepted for the intermediate band of the intertidal zone, due to the taxonomic differences and the abundance of dominant species in the four seasons. The difference in the vertical distribution of the intertidal benthic assemblages of both breakwaters highlights a distinct wave exposure condition, and reflects the breakwaters' orientation and the wave swell at each site.
Photobacterium damselae subsp. damselae, an emerging pathogen in Danish rainbow trout, Oncorhynchus mykiss (Walbaum), mariculture
Authors: Pedersen K , Skall H F , Lassen‐Nielsen A M , Bjerrum L , Olesen N J 
Published: April 2009

AbstractA selection of 16 field isolates of Photobacterium damselae from marine rainbow trout farms in Denmark was subjected to phenotypic and genotypic characterization and pathogenicity to fish. All isolates belonged to the subspecies damselae, being positive for haemolysis, motility and urease. There were considerable differences in haemolytic properties, some isolates presenting a broad zone of haemolysis and others only a narrow zone. Pulsed‐field gel electrophoresis revealed a high diversity indicating that P. damselae subsp. damselae is an opportunistic, not clonal pathogen in Danish marine rainbow trout. Virulence of the strains to rainbow trout was highly variable with LD50 values ranging from 3.9 × 103 to 1.5 × 108 cfu at 20 °C. The virulence was significantly higher at 20 °C than at 13 °C. The strains with the strongest haemolytic properties were the most virulent suggesting a strong involvement of haemolysin in the pathogenesis. The pathological changes were consistent with a bacterial septicaemia and the haemorrhages were more pronounced than for most other bacterial infections.
Some Common Fixed Point Theorems for Weakly Compatible Mappings in Metric Spaces
Authors: Ahmed M. A. 
Published: April 2009

AbstractWe establish a common fixed point theorem for weakly compatible mappings generalizing a result of Khan and Kubiaczyk (1988). Also, an example is given to support our generalization. We also prove common fixed point theorems for weakly compatible mappings in metric and compact metric spaces.
What's Happening in YA Literature? Trends in Books for Adolescents
Authors: Koss Melanie D. , Teale William H. 
Published: April 2009

Recent years have witnessed a surge of interest and activity in the field of young adult literature. In order to describe the types of young adult books being published currently, a systematic content analysis was undertaken on of a wide sample of titles published in English between 1999 and 2005 representing both high quality literature and books popular with teens. This article reports on trends found in the genres, descriptive features, subject matters, and writing styles of the books.ملخص البحث: لقد شهدت السنوات الأخيرة طفرة في الاهتمام والنشاط في مجال الأدب للشباب. لقد تم القيام بتحليل المحتوى والتنظيم من أجل وصف أنواع الكتب للشباب التي تنشر حالياً من عينة عريضة مختارة من عناوين الكتب المنشورة في اللغة الإنكليزية بين عامي 1999 و2005 تمثّل فيها كتباً ذات الجودة العالية والكتب التي تتمتع بشعبية كبيرة مع المراهقين. إذ تنقل هذه المقالة خبراً عن النزعات الموجودة في أنواع الكتب ومعالمها ومواضيعها وأساليبها الكتابية.对年轻成人文学领域的兴趣及其活动近年来有所激增。为描述当今出版发行的年轻成人书籍的种类，研究者对1999年和2005年间以英语出版的广大书籍样本，进行一项系统性的内容分析﹔该书籍样本代表了既是高质量的文学作品，又是青少年的流行读物。本文报告关于这些书籍的体裁、描述特点、题材和写作风格的趋势。Les dernières années ont témoigné d'un regain d'intérêt et d'activité dans le champ de la littérature de jeunesse. Afin de décrire les types de livres pour les jeunes adultes publiés récemment, nous avons entrepris une analyse systématique de contenu portant sur un large éventail de titres publiés en anglais de 1999 à 2005 et représentant à la fois la littérature de bonne qualité et des livres bien connus des jeunes. Cet article rapporte les tendances que nous avons trouvées dans les genres, les traits caractéristiques, les sujets traités, et les styles d'écriture des livres.В последние годы зафиксирован всплеск интереса и активности в области литературы для молодежи. Что именно сейчас издается? Чтобы ответить на этот вопрос, авторы предприняли системный содержательный анализ большой выборки книг, изданных на английском языке между 1999 и 2005 годами, куда вошли и высококачественные литературные произведения, и книги, популярные среди подростков. В статье описаны основные жанровые и содержательные тенденции, а также особенности авторского стиля и художественного оформления этих книг.Los últimos años han visto gran interés y actividad en el campo de la literatura para adultos jóvenes. Para poder describir las clases de libros que se están publicando ahora para adultos jóvenes, se emprendió un análisis sistemático del contenido de una muestra extensa de títulos publicados en inglés entre 1999 y 2005, tanto de libros de gran calidad como de libros populares entre los adolescentes. Este artículo da información sobre las tendencias en los géneros, las descripciones que presentan, el material y el estilo de escritura de los libros.
The Impact of Internet and Television Use on the Reading Habits and Practices of College Students
Authors: Mokhtari Kouider , Reichard Carla A. , Gardner Anne 
Published: April 2009

How much time do college students spend reading for recreational and academic purposes? Do Internet and television use displace or interfere with reading time? In this study, we used an innovative time‐diary survey method to explore whether the time students spend on the Internet or watching television displaces time that would be spent reading for academic or recreational purposes.كم من الوقت يقضي طلاب الجامعة في القراءة لأسباب المطالعة والدراسة؟ هل استخدام التلفاز أو الشبكة العالمية يحل محل القراءة أو يتدخل فيها؟ في هذه الدراسة استخدمنا مسحاً مبدعاً قائماً على كتابة يوميات بصدد قضاء الوقت كي نستقصي إذا كان الوقت الذي يقضي فيه الطلاب على الشبكة العالمية أو مشاهدة التلفاز يحل محل الوقت الذي كانوا قد سيقضوه بالقراءة لأسباب الدراسة أو المطالعة.大学生究竟花多少时间于为消遣和为学术目的而阅读？互联网和电视的使用有没有取代或妨碍学生阅读的时间？在本研究中，我们采用一个创新的时间日记调查方法，以探究大学生花在互联网或看电视的时间有没有取代他们会用于为学术或为消遣目的而阅读的时间。Combien de temps les étudiants de licence passent‐ils à lire à des fins récréatives et d'étude ? Est‐ce que l'utilisation d'Internet et de la télévision remplace ou interfère avec le temps consacré à la lecture ? Nous avons dans cette étude utilisé une méthode d'enquête innovante de journal budget‐temps quotidien pour savoir si le temps que les étudiants passent sur Internet ou à regarder la télévision remplace le temps qu'il auraient passé à lire à des fins récréatives ou d'étude.Сколько времени тратят студенты колледжа на развлекательное и академическое чтение? Оказывают ли Интернет и телевидение существенное воздействие на время, которые студенты посвящают чтению? В данном исследовании был использован инновационный метод – сочетание дневника учета времени и анкетирования, – который позволяет ответить на эти вопросы.¿Cuánto tiempo pasan los estudiantes colegiales leyendo, ya sea para entretenerse o para sus estudios? ¿Acaso la televisión y el Internet les quitan tiempo a estas actividades? En este estudio usamos un método innovador en forma de una encuesta de diario‐de‐tiempo para ver si el tiempo que los estudiantes pasan en el Internet o viendo televisión les quita tiempo que le hubieran dedicado a la lectura de recreo o de estudio.
Synthesis, Structure and Biological Activities of Some Novel Anthranilic Acid Esters Containing N‐Pyridylpyrazole
Authors: DONG Weili , XU Junying , XIONG Lixia , LIU Xinghai , LI Zhengming 
Published: April 2009

AbstractIn search of environmentally benign insecticides with high activity, low toxicity and low residue, a novel series of anthranilic acid esters containing N‐pyridylpyrazole were designed and synthesized. All of the compounds were characterized and confirmed by IR, 1H NMR, MS and elemental analysis. The single crystal structure of 14d was determined by X‐ray diffraction. The bioassay tests showed that the synthesized compounds exhibited good insecticidal activities against Mythimna separata Walker and Culex pipiens pallens.
Computational Study of the C‐ and N‐Bound Tautomers of [Ru(Cl)(H)(CO)‐(PPh3)2(IiPrMe2)] (IiPrMe2 = 3‐Isopropyl‐4,5‐dimethylimidazol‐2‐ylidene)
Authors: Häller L. Jonas L. , Macgregor Stuart A. 
Published: April 2009

AbstractDensity functional theory calculations have been used to study the factors controlling the relative energies of the C‐bound (2) and N‐bound (3) tautomers of [Ru(Cl)(H)(CO)(PPh3)2(IiPrMe2)] (IiPrMe2 = 3‐isopropyl‐4,5‐dimethylimidazol‐2‐ylidene) reported by Whittlesey and co‐workers (J. Am. Chem. Soc. 2006, 128, 13702). The calculations indicate that the N‐bound form is more stable. Further analysis reveals the presence of a CO ligand trans to the C/N binding site is a key factor in determining the greater stability of the N‐bound form. This preference is further enhanced by the bulky iPr substituent at the N3 position. The calculations predict that the C‐bound tautomer will be favoured with NHC ligands that feature a bulky C5 substituent in combination with small groups at N3 and C4. Thus [Ru(Cl)(H)(CO)(PPh3)2(NHC)] complexes where NHC = 5‐R‐imidazol‐2‐ylidene or 3‐Me‐5‐R‐imidazol‐2‐ylidene (R = tBu, Ph) are predicted to be more stable as the C‐bound form. Five‐coordinate square‐pyramidal species formed by loss of a CO or Cl ligand from 2 and 3 show an increased preference for the C‐bound form. Indeed, when the C/N binding site is trans to a vacant site the C‐bound tautomer becomes the more stable species.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Cyclodehydration of N‐[(2‐heteroarylcarbamoyl)methyl] benzamides. Preparation of 5‐(heteroarylamino)oxazoles
Authors: Glennon R. A. , Von Strandtmann M. 
Published: April 2009

AbstractThe cyclodehydration of N‐[heleroarylcarbamoyl)methyl]benzamides was found to yield 5‐(heteroarylamino)oxazoles
Cation radicals. XXXII. Reaction of N‐ethylcarbazole with iodine‐silver salts. Nitration of N‐ethylcarbazole
Authors: Bandlish B. K. , Shine H. J. 
Published: April 2009

AbstractReaction of N‐ethylcarbazole (1) with iodine‐silver perchlorate gave a green solution having a singlet esr signal. Reduction of the solution with potassium iodide gave N,N′ ‐diethyl‐3,3′‐dicarbazolyl (3, 48%). Small amounts of 3‐iodo‐ (4) and 3,6‐diiodo‐N‐ethylcarbazole (5) were also obtained. Compounds 4 and 5 are believed to have been formed by electrophilic iodination of 1 by I2‐AgCIO4, whereas 3 appears to have been formed via the dimerization of 1.+. In accord with this, reaction of 1 with iodine‐silver nitrite gave 3‐nitro‐N‐ethylcarbazole (6, 61%), 9% of another nitro‐N‐ethylcarbazole (7), thought to be either 1‐ or 4‐nitro‐N‐ethylcarbazole, and 28% of 4. Thus, trapping of 1.+ by nucleophilic nitrite ion occurred even though 1.+ is not stable enough toward isolation as the perchlorate.
The synthesis of some derivatives of 4,5,6,6a,7,12‐hexahydroisoquinolino [8,l ‐ab]carbazole
Authors: Bremner J. B. , Browne E. J. 
Published: April 2009

AbstractAs part of a general project on the chemistry of alkaloid analogues, the synthesis of derivatives 5, of 4,5,6,6a,7,12‐hexahydroisoquinolino[8,l‐ab]carbazole, which can be considered as ring D indole analogues of the aporphine skeleton, was investigated. Compounds of this type are of interest on two grounds. Firstly it is conceivable some may occur naturally; and secondly, they may display unusual pharmacological properties, since the side‐chain configuration of the tryptophan residue is intermediate between that present in lysergic acid diethylamide and the yohimbine‐reserpine type alkaloids.
Heterocycles. CXXVII. Action of sulfur on some heterocyclic compounds. Formation of thioamides, oxidative cyclization and thiation
Authors: Kramberger L. , Lorenčak P. , Polanc S. , Verček B. , Stanovnik B. , Tišler M. , Považanec F. 
Published: April 2009

AbstractThe formation of heterocyclic thioamides from alkylpyridines, heteroaromatic amines and sulfur was investigated. Oxidative cyclization of these thioamides afforded the corresponding thiazoloazines. Attempted thiation of some hydrazones gave triazolopyridines and some examples of direct thiation of heterocycles are given.
Isothiazoles. III. Synthesis of isothiazolo [5,4‐d] pyrimidines
Authors: Anderson Richard C. , Hsiao Y. Y. 
Published: April 2009

Abstract5‐Amino‐3‐methylisothiazole‐4‐carbonitrile 2 was prepared by oxidation of 3‐amino‐2‐cyano‐thiocrotonamide 1. A series of 4‐amino‐3‐methylisothiazolo[5,4‐d]pyrimidines 6 was derived from 2 by reaction with orthoesters followed by cyclization with primary amines. Hydrolysis of 2 to the corresponding amide 10 followed by cyclization with orthoesters gave the corresponding 5H‐isothiazolo[5,4‐d]pyrimidin‐4‐ones 11. Reactions of 2 and 10 with sodium methyl xanthate gave the corresponding pyrimidinethione derivatives 12 and 13.
The synthesis of some 2,4‐benzodiazepin‐1‐ones, potent C.N.S. agents
Authors: Golik Uri 
Published: April 2009

AbstractThe synthesis of 2,4‐benzodiazepin‐1‐ones (II, V) has been accomplished. Their C.N.S. properties are of the same order of the well known 1,4‐benzodiazepins (Valium).
Thiénopyrimidines VIII. Etude des thiéno[2,3‐d] pyrimidinethiones
Authors: Robba Max , De Sevricourt Michel Cugnon 
Published: April 2009

AbstractLes réactions de substitution et d'addition des thiéno[2,3‐d]pyrimidinethiones sont étudiées. Elles conduisent à des dérivés S‐ et N‐substitués dont la structure est établic par voie chimique ainsi qu'à l'aide des spectres IR et de RMN.
4‐Nitrosoquinoline 1‐oxide
Authors: Abramovitch Rudolph A. , Smith Elizabeth M. 
Published: April 2009

AbstractThe title compound has been synthesized by the oxidation of 4‐hydroxylaminoquinoline 1‐oxide with silver carbonate on celite. Some of its chemical properties have been studied and compared with those of 4‐nitrosopyridine 1‐oxide. Its mass spectrum and those of related compounds are discussed.
Mononuclear isoheterocyclic rearrangements. Note I. Interconversion of 3‐benzoylamino‐5‐methyl‐1,2,4‐oxadiazole and 3‐acetylamino‐5‐phenyl‐1,2,4‐oxadiazole
Authors: Vivona Nicolò , Cusmano Giuseppe , Ruccia Michele , Spinelli Domenico 
Published: April 2009

AbstractThe first example of mononuclear isoheterocyclic rearrangement is reported. The 3‐benzoylamino‐5‐methyl‐1,2,4‐oxadiazole (5) furnishes through a reversible process (slowly at room temperature in methanol, acetone or dioxane, fast in DMSO or in methanol in the presence of strong bases) a mixture of 5 and 3‐acethylamino‐5‐phenyl‐1,2,4‐oxadiazole (6). The equilibrium process can be achieved also by heating 5 at 181° and the same reaction mixture can be obtained using 6 as the starting material. 3‐Trichloroacetylamino‐5‐methyl‐1,2,4‐oxadiazole (7) was unaffected by similar treatment. The results obtained are discussed.
Synthesis of substituted 3‐amino[6,5‐b]triazinoindoles
Authors: Bell Malcolm R. , Zalay Andrew W. 
Published: April 2009

Abstract4‐[(9‐Methyl‐as‐triazino[6,5‐b]indol‐3‐yl)amino]‐2‐methyl‐2‐butanol (13) and the corresponding 2‐methyl‐3‐imino derivative 12 were synthesized and tested in vitro against Rhino 2 virus. The two compounds were more active than the known triazino[5,6‐b]indole 4. 2,9‐Dimethyl‐3‐methoxy‐9H‐as‐triazino[6,5‐b]indolium tosylate (21) and the related 3‐methylthio compound 9 were prepared. Quaternary 21 formed a pseudo base, 22a, whereas quaternary 9 did not form a pseudo base.
Propriétés chimiques du benzisosélénazole‐1,2
Authors: Weber Roland , Reason Marcel 
Published: April 2009

AbstractLa nitration et la bromation du benzisosélénazole‐1,2 conduit aux dérivés monosubstitués en 5 ou en 7. Par action de l'amidure de potassium sur l'hétérocycle non substitué on obtient le dérivé aminé en‐3 correspondant. Les dérivés organolithiens conduisent à une ouverture du cycle. La synthèse de dérivés substitués en 3à partir de styryl‐3 benzisosélénazole‐1,2 et sélénonaphtène quinone est aussi décrite.
1H‐imidazo[4,5‐b] pyrazines. 1. 2‐Alkyl derivatives
Authors: Tong Y. C. 
Published: April 2009

AbstractA group of 2‐alkyl‐1H‐imidazo[4,5‐b]pyrazines were prepared by condensing diamonpyrazines with acid, acid chloride or acid anhydride.
The reaction of o‐phthalaldchydic acid with 5‐amino‐1,3‐dimethylpyrazole
Authors: Swett Leo R. , Aynilian George H. 
Published: April 2009

Abstracto‐Phthalaldchydic acid reacted with 5‐amino‐1,3‐dimethylpyrazole to yield 5‐amino‐1,3‐dimethyl‐4‐phthalidylpyrazole. The latter was transformed to a tricyclic system; 1,3‐dimethylpyrazolo [3,4‐b]benzazepin‐9‐one, which in turn was reduced with lithium aluminum hydride to 9,10‐dihydro‐1,3‐dimethylpyrazolo[3,4‐b]benzazepine.
Attempted synthesis of 2,4‐ and 1,3‐benzodiazepinones
Authors: Golik Uri , Taub William 
Published: April 2009

AbstractThe cyclodehydration reaction performed upon α‐acylamino carboxamides is known to constitute a facile synthetic approach to five‐membered heterocyclic systems. Attempts to prepare 2,4‐ and 1,3‐benzodiazepinone derivatives (VI, XIX) of potential C.N.S. Activity using such methods, proved unsuccessful. A new triazine system (X) which was prepared did not exhibit any C.N.S. activity.
Benzopyranopyridine derivatives 3. Reaction of 1‐azaxanthone with grignard reagents
Authors: Villani Frank J. , Magatti Charles V. 
Published: April 2009

AbstractThree different classes of compounds were isolated in the reaction of Grignard reagents with 5‐H[1]benzopyrano[2,3‐b]pyridin‐5‐one, commonly called 1‐azaxanthone. The formation of (a) 4‐substituted 1,4‐dihydro‐1‐azaxanthones (II), (b) 5‐substituted‐5‐hydroxy‐1‐azaxanthenes (III) or (c) 4,5‐disubstituted‐1‐azaxanthenes (IV) is dependent on the solvent used in the preparation of the Griganrd reagent (i.e. ether or tetrahydrofuran), the steric properties of the reagent and on the temperature. The isolated compounds were characterized by chemical derivatives and/or spectroscopic analyses.
Studies in the heterocyclic series. XI. Reactions of 2‐Amino‐3‐hydroxypyridine with 2‐Chloro‐3‐nitropyridine
Authors: Okafor Charles O. 
Published: April 2009

AbstractThe reactions of 2‐amino‐3‐hydroxypyridine and 2‐chloro‐3‐nitropyridine in various solvents and in the presence of certain catalysts were studied. A dilute acid‐catalysed procedure led to a 45% yield of 3‐hydroxy‐3‐nitro‐2,2‐dipyridylamine which was also obtained by refluxing in alcoholic potassium hydroxide for several hours. The diarylamine was converted to 1,9‐diazaphenoxazine by base‐catalysed intramolecular condensation in refluxing DMSO. The same diazaphenoxazine was obtained directly by prolonged base‐catalysed reaction of the starting pyridine compounds in DMSO. From a study of the infrared spectrum of the diarylamine precursor, it was found that strong NHO hydrogen bonding is responsible for the failure of the cyclization step in either aqueous or alcoholic base. This problem was overcome by the use of DMSO as the reaction solvent. Structural assignments were made by a study of their ultraviolet, infrared, nmr and mass spectra and the mechanistic pathways were also discussed.
Reactions of ketenes XVII. Intermediates in the reactions between ketone acetals and ethyl azidoformate
Authors: Graziano M. L. , Scarpati R. 
Published: April 2009

AbstractThe reaction of the ketene acetals with ethyl azidoformate proceeds via I‐ethoxycarbonyl‐5,5‐dialkoxy‐Δ2 ‐1,2,3‐triazolines. The latter decomposes easily at room temperature, the reaction pathway depending on the presence of the substituents at the 4‐position. Thermolysis and photolysis of the 4‐alkyl‐substituted triazolines proceed via 1,3‐diradicals. The photodecomposition of the 4‐unsubstituted triazolines proceeds similarly. The thermal decomposition of the latter is considered either to involve homolytic cleavage of the N1N2 bond to give a 1,5‐diradical, or to proceed by a concerted mechanism.
Spectres photoélectroniques de divers thiéno[2,3‐b] thiophènes
Authors: Coustale M. , Guimon C. , Arriau J. , Pfister‐Guillouzo G. 
Published: April 2009

AbstractLes spectres photoélectroniques de dérivés de monosuhstitution du thiéno[2,3‐b]thiophène (halogène et méthyle) out été analysés. Les attributions proposées sont confirmées par les effets des di, tri et tetrasubstitutions, et en bon accord avec un calcul CNDO/S.
Etude, par spectroscopie dans le visible, des complexes moleculaires du chloranile avec les derives de l'indole substitue en‐1,‐2 on‐3
Authors: Sabourault B. , Abenhaïm D. , Bourdais J. 
Published: April 2009

AbstractNous avons étudié par spectroscopie dans le visible les complexes moléculaires de différents indoles substitués en‐1,‐2 ou‐3 avec le chloranile dans le chloroforme, et calculé les constantes d'associations de ces complexes par la méthode de Benesi‐Hildebrand. L'influence du solvant sur les constantes d'association a éte également étudiée dans le cas des complexes méthyl‐2 indole chloranile. Nous avons enfin pu grâce à cette étude, accéder aux potentiels d'ionisations des indoles en utilisant la relation de Foster.
Thermal, photochemical and mass spectral reactions of 2‐ethyl‐5‐methyl‐1‐pyrroline
Authors: Mcdaniel D. M. , Benisch S. 
Published: April 2009

AbstractPyrolysis of 2‐ethyl‐5‐methylpyrroline (1) results in formation of 2,5‐dimethylpyrrole, 2‐ethyl‐5‐methylpyrrole, 2‐ethylpyrrole and other minor products. Loss of a hydrogen atom or methyl radicals is suggested as the first step in these reactions. Support for the former comes from hydrogen atom abstraction by photo‐excited benzophenone. The mass spectral reactions of 1 are briefly considered.
A new synthesis of ampicillin and related investigations
Authors: Kajfež F. , Kovač T. , Mihalić M. , Belin B. , Šunjić V. 
Published: April 2009

AbstractQuaternization of (S)‐α‐bromophenylacetic acid amide (8) with hexamethylentetramine (hexamine) preceded with ca. 80% inversion of configuration. Accordingly, starting from the trimethylsilylester of N‐(S)‐(α‐bromo‐α‐phenylacetyl)‐6‐aminopenicillanic acid (4) quaternization with hexamine and subsequent hydrolysis afforded N‐(R)‐α‐phenylglycyl‐6‐aminopenicillanic acid (1, ampicillin). Some other model reactions have been investigated.