bluuebunny/crossref_metadata_2025 huggingface dataset:
Refinement of the free radial forearm flap reconstructive technique after resection of large oropharyngeal malignancies with excellent functional results
Authors: Moerman Mieke , Vermeersch Hubert , Van Lierde Kristiane , Fahimi Hossein , Van Cauwenberge Paul
Published: September 2003

Background.

Wide resection of oropharyngeal malignancies implicates the risk of velopharyngeal insufficiency, which can cause nasal regurgitation and hypernasality. A meticulous reconstruction is necessary to avoid impairment and handicap in deglutition and speech. In the classic reconstructive techniques for large oropharyngeal defects, functional outcome only regards deglutition. We also focus on nasality, because hypernasality often occurs as a consequence in this type of reconstruction.

Methods.

In four patients, the surgical defect is closed with a free radial forearm flap sutured to the posterior side of the hard palate, thus imitating a caudally based pharyngeal flap. Speech is assessed by an independent speech pathologist, perceptually and acoustically. Deglutition is evaluated by a questionnaire and videofluoroscopy.

Results.

All patients had normal food intake. They did not report alterations in speech quality or verbal communication. Perceptual evaluation of articulation, voice, and nasality was optimal. Objective measurements with acoustical analysis and nasality scores confirmed the excellent functional outcome. Videofluoroscopy showed an unimpaired bolus transport with a complete velopharyngeal closure and optimal oral and pharyngeal clearance times.

Conclusions.

This meticulous reconstructive technique ensures an excellent functional outcome. The absence of nasality, in particular, proves the value of this refinement. The technique allows wide surgical margins and complete velopharyngeal closure. © 2003 Wiley Periodicals, Inc. Head Neck 25: 772–777, 2003
Sclerosing cervicitis: Report of a skull base lesion with literature review
Authors: Deussing Eric C. , Daroca Philip J. , Nemechek Andrew J.
Published: September 2003

Background.

Invasive fibrosclerotic lesions of the head and neck outside of the thyroid and orbit are extremely rare. To date 13 cases of sclerosing cervicitis have been described in the literature.

Methods.

We present a case of a sclerosing inflammatory lesion encountered at the skull base in a 49‐year‐old woman.

Results.

After surgical excision and pathologic examination, this lesion was identified as sclerosing cervicitis.

Conclusions.

This case report contributes to an awareness of a rare lesion of the head and neck that presents clinical and treatment challenges for surgeons managing these patients. © 2003 Wiley Periodicals, Inc. Head Neck 25: 778–783, 2003
Crystalline Corrugation in Multilayer Films on Aqueous Subphases
Authors: Buller R. , Weissbuch I. , Cohen S. , Kjaer K. , Lahav M. , Leiserowitz L.
Published: September 2003

A strong Bragg peak, attributed to regular corrugation in a crystalline film, was detected in a series of self‐assembled supramolecular complexes of bifunctional bolaamphiphiles of different lengths, with divalent ions of Pb and Cu, at the airaqueous interface. This peak has a d spacing half that of the proposed corrugation‐repeat length of ca. 82 Å, which is not a multiple of the long lattice spacing of the crystalline structure, and is susceptible to film compression. This corrugation is interpreted in terms of unfavorable interactions between the polar aqueous surface and the nonpolar hydrocarbon part of the bolaamphiphiles. To establish the nature of the corrugation, grazing‐incidence X‐ray diffraction and specular X‐ray reflectivity with synchrotron radiation were applied, as well as scanning force microscopy of films deposited on mica.
Synthesis and Enzymic Hydrolysis of Oligoribonucleotides Incorporating 3‐Deazaguanosine: The Importance of the Nitrogen‐3 Atom of Single Conserved Guanosine Residues on the Catalytic Activity of the Hammerhead Ribozyme
Authors: Seela Frank , Debelak Harald , Andrews Lori , Beigelman Leonid
Published: September 2003

Four base‐modified hammerhead ribozyme/substrate complexes were constructed in which single guanosine (1) residues were replaced by 3‐deazaguanosine (2) in the positions G5, G8, GL2.1, and G12. The base‐modified ribozyme complexes were prepared by solid‐phase synthesis of oligoribonucleotides employing the novel phosphoramidite 3 derived from 2. Phosphoramidite 3 carried a phenoxyacetyl group at the amino function and a diphenylcarbamoyl residue at the oxo group of the nucleobase. The 2′‐hydroxy group was blocked with a triisopropylsilyl residue. Kinetic analysis of the phosphodiester hydrolysis showed a moderate decrease of the ribozyme catalytic activity when the residues G5 or G8 were replaced by 3‐deazaguanosine and a 200‐fold decrease when G12 was substituted. A 6‐fold catalytic increase occurred when 3‐deazaguanosine was replacing GL2.1 in the loop region. The data indicate that the N(3) atom of compound 2, in particular at position G12 is critical for the ribozyme activity.
Convergent Approaches to Saudin Intermediates
Authors: Cravero Raquel M. , González‐Sierra Manuel , Labadie Guillermo R.
Published: September 2003

Different convergent approaches to the highly oxygenated sesquiterpene natural product saudin (1), has been investigated. Our strategy has included a Michael addition and aldol condensation reaction as key steps. During the synthetic development, we have found serious steric hindrance when an α‐Me‐substituted alkyl vinyl ketone was used. Such steric hindrance has been overcome by synthesizing the vinyl ketone 16 through an anionic fragmentation, which was carefully studied. Finally, the intermediate 18 has been synthesized in a one‐pot reaction from the vinyl ketone 16 and has been cyclized to obtain the promising tricyclic intermediate 20.
Synthesis of Novel (Phenylalkyl)amines for the Investigation of StructureActivity Relationships, Part 3
Authors: Trachsel Daniel
Published: September 2003

An easy and efficient pathway for the preparation of 4‐ethynyl‐2,5‐dimethoxyphenethylamine (=4‐ethynyl‐2,5‐dimethoxybenzeneethanamine; 2C‐YN; 1) was developed, an ethynyl analogue of the potent 5‐HT2A/C agonists, e.g., 4‐iodo‐2,5‐dimethoxy‐amphetamine (DOI; 2b). The ethynyl moiety was introduced by a Pd‐catalyzed Sonogashira reaction of (trimethylsilyl)ethyne with N‐(trifluoroacetyl)‐protected 4‐iodo‐2,5‐dimethoxyphenethylamine (7) in almost quantitative yield within only 1 h. Removal of the Me3Si group was accomplished with Bu4NF. Final N‐deprotection by NaOH treatment afforded the novel phenethylamine 1 in an overall yield of 88%.
Two New Insecticidal Amides and a New Alcoholic Amide from Piper nigrum Linn.
Authors: Siddiqui Bina S. , Gulzar Tahsin , Begum Sabira , Rasheed Munawwer , Sattar Fouzia A. , Afshan Farhana
Published: September 2003

Three new amides, pipgulzarine (1), pipzorine (2), and piptahsine (3), have been isolated from the dried seeds of Piper nigrum Linn. along with nine known constituents: (2E,4E,8Z)‐N‐(isobutyl)eicosatrienamide, pellitorine, pipercide, piperine, stigmastanol, stigmasterol, decurrenal, stigmasterol 3‐O‐β‐D‐glucopyranoside, and 5,10(15)‐cadinen‐4‐ol. The structures of the new constituents have been established as (2E,11E)‐12‐(benzo[1,3]dioxol‐5‐yl)‐N‐(2‐methylpropyl)dodeca‐2,11‐dienamide (1), (2E,12Z)‐N‐(4‐methylpentyl)octadeca‐2,12‐dienamide (2), and (2E,4S)‐4‐hydroxy‐N‐(2‐methylpropyl)hex‐2‐enamide (3). The structures of 1–3 were derived by spectral studies and chemical reactions, and by comparison of spectral data in the case of known constituents. Compounds 1 and 2, and most of the already known compounds, exhibited toxicity against fourth instar larvae of Aedes aegypti Liston. The isolated (Z) double bond in 2 was assigned on the basis of its EI‐MS fragmentation pattern and its reaction with OsO4. The (S) configuration at C(4) of 3 was determined by Horeau's method. This is the first report of the isolation of a 4‐methylpentylamide from P. nigrum, while shorter branched amides have been reported from this genus [1].
Isolation and On‐Line LC/CD Analysis of 3,8″‐Linked Biflavonoids from Gnidia involucrata
Authors: Ferrari Julien , Terreaux Christian , Kurtán Tibor , Szikszai‐Kiss Attila , Antus Sándor , Msonthi Jerome D. , Hostettmann Kurt
Published: September 2003

Investigation of the methanol extract of the roots of Gnidia involucrata (Thymelaeaceae) led to the isolation and characterization of two new 3,8″‐biflavonoid diastereoisomers, named GB‐4 (6a) and GB‐4a (6b). Their absolute configurations were determined in mixture by on‐line LC/CD measurements, which also allowed the revision of absolute configurations of the biflavanoids GB‐1 and GB‐2, and the configurational assignment of GB‐3.
Competing Formations of Oxonium and Carbonyl Ylides with Carbonylcarbenes
Authors: Talinli E. Naciye , Anaç Olcay , Kumbaracı I. Volkan
Published: September 2003

A series of 2‐mono‐ and 2,2‐disubstituted 1,3‐dioxepin derivatives, two of which also had a carbonyl function in one of their 2‐R groups, were prepared and reacted with dimethyl diazomalonate with copper(II) acetylacetonate as a catalyst. Ylide formation probabilities with allyl ether and/or carbonyl functions were investigated. A chemoselectivity in favor of carbonyl ylide was observed.
Triptowilfolide, a Novel Compound from Tripterygium wilfordii
Authors: Luo Duqiang , Zhang Xing , Tian Xuan , Liu Jikai
Published: September 2003

A novel diterpenoid‐related compound, triptowilfolide (1), was isolated from the root bark of the Tripterygium wilfordii. Its structure was established by spectroscopic means.
Chemical Constituents of the Flowers of Azadirachta indica
Authors: Siddiqui Bina S. , Ali Syed Tariq , Rasheed Munawwer , Kardar Muhammad Nadeem
Published: September 2003

Studies on the chemical constituents of the flowers of Azadirachta indica have led to the isolation of two new flavanones, flowerine (=5‐hydroxy‐7,4′‐dimethoxy‐8‐(3‐methylbut‐2‐enyl)flavan‐4‐one; 1) and flowerone (=5,7,8,4′‐tetrahydroxy‐3′‐(3‐methylbut‐3‐enyl)flavan‐4‐one; 2), and two new triterpenoids, O‐methylazadironolide (=7α‐(acetoxy)‐23ξ‐methoxy‐21,23‐epoxy‐24,25,26,27‐tetranorapotirucalla‐1,14,20(22)‐trien‐3,21‐dione; 3) and diepoxyazadirol (=(20S,23S,24R)‐7‐α‐(acetoxy)‐25‐hydroxy‐21,24 : 23,24‐diepoxyapotirucalla‐1,14‐dien‐3‐one; 4) along with the known triterpenoid trichilenone acetate (=7α‐(acetoxy)‐14,15 : 21,23‐diepoxy‐24,25,26,27‐tetranorapotirucalla‐1,20,22‐trien‐3‐one; 5), two known flavanones, nimbaflavone (=5,7‐dihydroxy‐4′‐methoxy‐8,3′‐bis(3‐methylbut‐2‐enyl)‐flavan‐4‐one; 6) and 3′‐prenylnaringenin (=5,7,4′‐trihydroxy‐3′‐(3‐methylbut‐2‐enyl) flavan‐4‐one; 7), and 4‐(2‐hydroxyethyl)phenol (8). Their structures have been elucidated through spectral studies, including 2D‐NMR experiments, and chemical transformation. Compounds 5, 7 and 8 are heretofore unreported from any part of tree, while 6 has been isolated earlier from leaves.
Chemical Constituents from the Roots of Schnabelia tetradonta
Authors: Dou Hui , Liao Xun , Peng Shu‐Lin , Pan Yuan‐Jiang , Ding Li‐Sheng
Published: September 2003

The new rearranged‐abietane diterpene 1, the four new triterpenoids 2–5, and the new aminoethylphenyl oligoglycoside 6, besides 19 known compounds, were isolated from the roots of Schnabelia tetradonta, a Chinese endemic herb. The structures of the new compounds were elucidated on the basis of spectroscopic evidence as 12,17‐epoxy‐11,14,16‐trihydroxy‐17(15→16)‐abeo‐abieta‐8,11,13,15‐tetraen‐7‐one (1), 21β‐(β‐D‐glucopyranosyloxy)‐2α,3α‐dihydroxyolean‐12‐en‐28‐oic acid (2), 2β,3β,16β‐trihydroxy‐15‐oxo‐28‐norolean‐12‐en‐23‐oic acid (3), 3β‐[(4‐O‐acetyl‐β‐D‐glucopyranuronosyl)oxy]‐2β,16β‐dihydroxy‐28‐norolean‐15‐oxo‐12‐en‐23‐oic acid (4), 3β‐[(4‐O‐acetyl‐6‐O‐methyl‐β‐D‐glucopyranuronosyl)oxy]‐2β,16β‐dihydroxy‐15‐oxo‐28‐norolean‐12‐en‐23‐oic acid (5), and 4‐[2‐(acetylamino)ethyl]phenyl O‐6‐O‐[(Z)‐p‐methoxycinnamoyl]‐β‐D‐glucopyranosyl‐(1→2)]‐O‐[β‐D‐glucopyranosyl‐(1→3)]‐4‐O‐acetyl‐α‐L‐rhamnopyranoside (6), respectively.
A Novel Synthetic Approach to (±)‐Desoxynoreseroline
Authors: Mekhael Maged K. G. , Heimgartner Heinz
Published: September 2003

(±)‐Desoxynoreseroline (3), the basic ring structure of the pharmacologically active alkaloid physostigmine (1), was synthesized starting from 3‐allyl‐1,3‐dimethyloxindole (9). The latter was prepared from the corresponding 2H‐azirin‐3‐amine 6 by a BF3‐catalyzed ring enlargement via an amidinium intermediate 7 (Scheme 1). An alternative synthesis of 9 was also carried out by the reaction of N‐methylaniline with 2‐bromopropanoyl bromide (12), followed by intramolecular Friedel–Crafts alkylation of the formed anilide 13 to give Julian's oxindole 11. Further alkylation of 11 with allyl bromide in the presence of LDA gave 9 in an excellent yield (Scheme 3). Ozonolysis of 9, followed by mild reduction with (EtO)3P, gave the aldehyde 14, whose structure was chemically established by the transformation to the corresponding acetal 15 (Scheme 4). Condensation of 14 with hydroxylamine and hydrazine derivatives, respectively, gave the corresponding imine derivatives 16a–16d as a mixture of syn‐ and anti‐isomers. Reduction of this mixture with LiAlH4 proceeded by loss of ROH or RNH2 to give racemic 3 (Scheme 5).
Synthesis of Branched Oligonucleotides as Templates for the Assembly of Nanomaterials
Authors: Grimau Marta G. , Iacopino Daniela , Aviñó Anna , de la Torre Beatriz G. , Ongaro Andrea , Fitzmaurice Donald , Wessels Jurina , Eritja Ramon
Published: September 2003

Branched oligonucleotides with symmetric arms 6–15, which may contain biotin as a second recognition code, were prepared. These molecules are designed to be used for the directed assembly of nanomaterials. The branched structure of the desired oligonucleotides was confirmed by mass spectrometry on small branched oliognucleotides, by gel electrophoresis, and by hybridization with complementary oligonucleotidenanoparticle conjugates, followed by visualization of the complexes by transmission electron microscopy.
Enzymatic Synthesis of Nucleoside‐5′‐O‐(1‐thiophosphates) and (SP)‐Adenosine‐5′‐O‐(1‐thiotriphosphate)
Authors: Barai Vladimir N. , Zinchenko Anatoli I. , Kvach Sergei V. , Titovich Olga I. , Rubinova Elena B. , Kalinichenko Elena N. , Mikhailopulo Igor A.
Published: September 2003

Treatment of adenosine with PSCl3 in trimethyl phosphate gave, after ion‐exchange chromatography, adenosine‐5′‐O‐monophosphate (AMP; 28%) and adenosine‐5′‐O‐monothiophosphate (AMPS; 48%). AMPS was studied as a thiophosphate residue donor in an enzymatic transphosphorylation with nucleoside phosphotransferase (NPase) of the whole cells of Erwinia herbicola. As exemplified by a number of natural and sugar‐ and base‐modified nucleosides, it was demonstrated that NPase of the whole cells of Erwinia herbicola catalyzes the transfer of both thiophosphate and phosphate residues with a similar efficiency. An incubation of AMPS in a phosphorylating extract of Saccharomyces cerevisiae (K‐phosphate buffer (0.3 M, pH 7.0); 3% glucose; 15 mM MgCl2; 28°, 8 h), followed by ion‐exchange column chromatography afforded AMP (8%), AMPS (recovered, 23%), ATP (11%), and (SP)‐adenosine‐5′‐O‐(1‐thiotriphosphate) ((SP)‐ATPαS); (total yield 37%; 48% based on the consumed AMPS). For comparison of physicochemical properties, adenosine was chemically transformed into ATPαS as a mixture of the (SP) (53%) and (RP) (44%) diastereoisomers.
1,3‐Oxathiolanes from the Reaction of Aromatic and Enolized Thioketones with Monosubstituted Oxiranes
Authors: Fu Changchun , Linden Anthony , Heimgartner Heinz
Published: September 2003

The reactions of 4,4′‐dimethoxythiobenzophenone (1) with (S)‐2‐methyloxirane ((S)‐2) and (R)‐2‐phenyloxirane ((R)‐6) in the presence of a Lewis acid such as BF3⋅Et2O, ZnCl2, or SiO2 in dry CH2Cl2 led to the corresponding 1 : 1 adducts, i.e., 1,3‐oxathiolanes (S)‐3 with Me at C(5), and (S)‐7 and (R)‐8 with Ph at C(4) and C(5), respectively. A 1 : 2 adduct, 1,3,6‐dioxathiocane (4S,8S)‐4 and 1,3‐dioxolane (S)‐9, respectively, were formed as minor products (Schemes 3 and 5, Tables 1 and 2). Treatment of the 1 : 1 adduct (S)‐3 with (S)‐2 and BF3⋅Et2O gave the 1 : 2 adduct (4S,8S)‐4 (Scheme 4). In the case of the enolized thioketone 1,3‐diphenylprop‐1‐ene‐2‐thiol (10) with (S)‐2 and (R)‐6 in the presence of SiO2, the enesulfanyl alcohols (1′Z,2S)‐11 and (1′E,2S)‐11, and (1′Z,2S)‐13, (1′E,2S)‐13, (1′Z,1R)‐15, and (1′E,1R)‐15, respectively, as well as a 1,3‐oxathiolane (S)‐14 were formed (Schemes 6 and 8). In the presence of HCl, the enesulfanyl alcohols (1′Z,2S)‐11, (1′Z,2S)‐13, (1′E,2S)‐13, (1′Z,1R)‐15, and (1′E,1R)‐15 cyclize to give the corresponding 1,3‐oxathiolanes (S)‐12, (S)‐14, and (R)‐16, respectively (Schemes 7, 9, and 10). The structures of (1′E,2S)‐11, (S)‐12, and (S)‐14 were confirmed by X‐ray crystallography (Figs. 1–3). These results show that 1,3‐oxathiolanes can be prepared directly via the Lewis acid‐catalyzed reactions of oxiranes with non‐enolizable thioketones, and also in two steps with enolized thioketones. The nucleophilic attack of the thiocarbonyl or enesulfanyl S‐atom at the Lewis acid‐complexed oxirane ring proceeds with high regio‐ and stereoselectivity via an Sn2‐type mechanism.
The Nonchiral Bislactim Diethoxy Ether as a Highly Stereo‐Inducing Synthon for Sterically Hindered, γ‐Branched α‐Amino Acids: A Practical, Large‐Scale Route to an Intermediate of the Novel Renin Inhibitor Aliskiren
Authors: Göschke Richard , Stutz Stefan , Heinzelmann Walter , Maibaum Jürgen
Published: September 2003

The diastereoselective synthesis of the sterically hindered, γ‐branched α‐amino acid derivative (2S,4S)‐24a and its N‐[(tert‐butoxy)carbonyl](Boc)‐protected alcohol (2S,4S)‐19, both key intermediates of a novel class of nonpeptide renin inhibitors such as aliskiren (1), is described. Initially, the analogous methyl ester (2S,4S)‐17 was obtained by alkylation of the chiral Schöllkopf dihydropyrazine (R)‐12a with the dialkoxy‐substituted alkyl bromide (R)‐11a, which proceeded with explicitly high diastereofacial selectivity (ds ≥98%) to give (2S,5R,2′S)‐13a (Scheme 4), followed by mild acid hydrolysis and N‐Boc protection (Scheme 5). Conversely, the complete lack of stereocontrol and poor yields for the reaction of (R)‐11a with the enantiomeric (S)‐12b suggested, in addition to the anticipated shielding effect by the iPr group at C(2) of the auxiliary, steric repulsion between the MeOC(6) and the bulky residues of (R)‐11a in the proposed transition state, which would strongly disfavor both the Si and Re attack of the electrophile (see Fig.). Based on this rationale, alkylation of the readily accessible achiral diethoxy‐dihydropyrazine 21 with (R)‐11a was found to provide a 95 : 5 mixture of diastereoisomers (2S,2′S)‐22a and (2R,2′S)‐23a in high yield (Scheme 6), which afforded in two steps and after recrystallization enantiomerically pure (2S,4S)‐24a. Similarly, the stereochemical course for the alkylation reactions of the related alkyl bromides (S)‐28a and (R)‐28b with both (R)‐12a and (S)‐12b as well as with the achiral 21 was investigated (Schemes 7–9). The precursor bromides (R)‐11a, (S)‐11b, (R)‐28a, and (S)‐28b were efficiently synthesized via the diastereoselective alkylation of the Evans 3‐isovaleroyloxazolidin‐2‐ones (R)‐7a and (S)‐7b either with bromide 6 or with benzyl chloromethyl ether, and subsequent standard transformations (Schemes 3 and 7). A practical and economical protocol of the preparation of (2S,4S)‐24a on a multi‐100‐g scale is given. This is the first report of the application of an achiral dihydropyrazine, i.e., in form of 21, as a highly stereo‐inducing synthon providing rapid access to a N‐protected γ‐branched α‐amino acid with (2S) absolute configuration.
Controlled Release of Perfumery Alcohols by Neighboring‐Group Participation. Comparison of the Rate Constants for the Alkaline Hydrolysis of 2‐Acyl‐, 2‐(Hydroxymethyl)‐, and 2‐Carbamoylbenzoates
Authors: de Saint Laumer Jean‐Yves , Frérot Eric , Herrmann Andreas
Published: September 2003

A series of 2‐acylbenzoates 1 and 2, 2‐(hydroxymethyl)benzoates 3, 2‐carbamoylbenzoates 4–6, as well as the carbamoyl esters 7 or 8 of maleate or succinate, respectively (see Fig. 2), were prepared in a few reaction steps, and the potential use of these compounds as chemical delivery systems for the controlled release of primary, secondary, and tertiary fragrance alcohols was investigated. The rate constants for the neighboring‐group‐assisted alkaline ester hydrolysis were determined by anal. HPLC in buffered H2O/MeCN solution at different pH (Table 1). The rates of hydrolysis were found to depend on the structure of the alcohol, together with the precursor skeleton and the structure of the neighboring nucleophile that attacks the ester function. Primary alcohols were released more rapidly than secondary and tertiary alcohols, and benzoates of allylic primary alcohols (e.g., geraniol) were hydrolyzed 2–4 times faster than their homologous saturated alcohols (e.g., citronellol). For the same leaving alcohol, 2‐[(ethylamino)carbonyl]benzoates cyclized faster than the corresponding 2‐(hydroxymethyl)benzoates, and much faster than their 2‐formyl and 2‐acetyl analogues (see, e.g., Fig. 4). Within the carbamoyl ester series, 2‐[(ethylamino)carbonyl]benzoates were found to have the highest rate constants for the alkaline ester hydrolysis, followed by unsubstituted 2‐(aminocarbonyl)benzoates, or the corresponding isopropyl derivatives. To rationalize the influence of the different structural changes on the hydrolysis kinetics, the experimental data obtained for the 2‐[(alkylamino)carbonyl]benzoates were compared with the results of density‐functional computer simulations (Table 2 and Scheme 4). Based on a preliminary semi‐empirical conformation analysis, density‐functional calculations at the B3LYP/6‐31G** level were carried out for the starting precursor molecules, several reaction intermediates, and the cyclized phthalimides. For the same precursor skeleton, these simple calculations were found to model the experimental data correctly. With an understanding of the influence of structural parameters on the rate constants obtained in this work, it is now possible to influence the rates of hydrolysis over several orders of magnitude, to design tailor‐made precursors for a large variety of fragrance alcohols, and to predict their efficiency as controlled‐release systems in practical applications.
Synthesis of Psoralen Analogues Based on Dibenzofuran
Authors: Oliveira Ana M. A. G. , Raposo M. Manuela M. , Oliveira‐Campos Ana M. F. , Griffiths John , Machado Antonio E. H.
Published: September 2003

The syntheses of four novel psoralen derivatives, 6a–d, of the benzofurocoumarin (=benzofuro[1]benzopyranone) type containing an ester group are described. These compounds might be of interest in PUVA (psoralen long‐wave ultraviolet radiation) therapy. The overall efficiency of the synthetic procedure is greatly limited by the low yields for the penultimate step, i.e., formylation of the dibenzofuranols 3a,c or protected dibenzofuranol 4d to the carboxaldehydes 5 (Scheme 4). However, the final stage to form the pyranone ring from 5a–d proceeds smoothly (Scheme 5).
Crystal Structure and Chemical Stabilization of the Triple Salt (KHSO5)2⋅KHSO4⋅K2SO4
Authors: Ermer Otto , Röbke Christof
Published: September 2003

The title compound, a versatile and chemically stabilized oxidant, which is used technologically on a large scale, builds up an intercalation‐type of crystal structure with alternating sheets of sulfate and peroxomonosulfate anions, interspersed by the potassium cations. The sulfate ions are joined by a very short but nonetheless probably asymmetric hydrogen bond. At room temperature, the HSO$\rm{_{5}^{-}}$ ions show dynamic orientational/conformational disorder in the area of the hydrogenperoxo group, which disappears at 100 K. The chemical stabilization of the triple salt is ascribed to shielding of the HSO$\rm{_{5}^{-}}$ ions effected by the intercalation between the sulfate sheets and, furthermore, by the large and abundant K+ ions of this potassium‐rich compound.
Indoloquinazoline Alkaloids from Araliopsis tabouensis
Authors: Christopher Ezugwu , Bedir Erdal , Dunbar Chuck , Khan Ikhlas A. , Okunji Christopher O. , Schuster Brian M. , Iwu Maurice M.
Published: September 2003

Three new indoloquinazolidine‐type alkaloids, 8,13‐dihydro‐2‐methoxyindolo[2′,3′: 3,4]pyrido[2,1‐b]quinazolin‐5(7H)‐one (1), 8,13‐dihydro‐2‐methoxy‐13‐methylindolo[2′,3′: 3,4]pyrido[2,1‐b]quinazolin‐5(7H)‐one (2), and 5,8,13,14‐tetrahydro‐2‐methoxy‐14‐methyl‐5‐oxo‐7H‐indolo[2′,3′: 3,4]pyrido[2,1‐b]quinazolim‐6‐iun chloride (3) were isolated from Araliopsis tabouensis, together with three known compounds. The structures of the new compounds were determined primarily from 1D‐ and 2D‐NMR analysis. The antimalarial activities of compounds 1–5 were evaluated against Plasmodium falciparum D6 and W2 clones. The IC50 values in antimalarial bioassay for compounds 2–5 varied from 1.8 to 4.7 μg/ml.
A Sensitive and Selective High‐Throughput Screening Fluorescence Assay for Lipases and Esterases
Authors: Nyfeler Erich , Grognux Johann , Wahler Denis , Reymond Jean‐Louis
Published: September 2003

Long‐chain fatty acid esters of 7‐(3,4‐dihydroxybutyloxy)‐2H‐1‐benzopyran‐2‐one (6) such as octanoate 2a are shown to be exceptionally sensitive and selective fluorogenic substrates for lipases and esterases. Umbelliferone (8) is released upon hydrolysis of the ester function in 2a in the presence of bovine serum albumin and sodium periodate. These substrates are at least by one order of magnitude more sensitive to lipases than the commercial fluorogenic substrate 4‐methylumbelliferyl heptanoate. Furthermore, they are stable to a broad range of pH‐induced‐ and thermal‐hydrolysis conditions and do not react with non‐catalytic proteins such as bovine serum albumin (BSA).
β‐Amino Alcohol Properfumes
Authors: Yang Yongzheng , Wahler Denis , Reymond Jean‐Louis
Published: September 2003

Amino‐alcohol derivatives of fragrant, volatile aldehydes and ketones were synthesized in a one‐pot procedure by sequential cyanohydrin formation with trimethylsilyl cyanide and reduction with lithium aluminium hydride, or by ammonolysis of epoxide precursors. The amino alcohols are nonvolatile, stable properfumes releasing fragrant carbonyls by oxidation with sodium periodate or sodium bismuthate. Examples include amino alcohol properfumes of citronellal,Lilial®, lauryl aldehyde, menthone, benzaldehyde, and anisaldehyde.
The influence of framing on attitudes toward diversity training
Authors: Holladay Courtney L. , Knight Jennifer L. , Paige Danielle L. , Quiñones Miguel A.
Published: September 2003

Although diversity training is becoming an integral component of organizations, little empirical research on
the topic exists. The study examined here investigated how framing of diversity training (title, focus of
content, assignment) and gender influenced participants' attitudes. In this study, 160 adults (72
men, 88 women; 124 white; 36 minority) read a diversity course description and answered questions assessing
their attitudes about the course and the organization. Results revealed that (1) a frame with a
traditional title and a broad focus was responded to most favorably by participants, (2) men reacted
more negatively than women to the diversity training course, and (3) men reacted more negatively than
women to a frame with a narrow focus and remedial assignment. Findings are discussed in terms of the effect that
different frames can have on participants' pretraining attitudes toward diversity training. Implications for
researchers and consultants are also discussed.
Determining the relationship between drivers' level of education, training, working conditions, and job performance in Kenya
Authors: Nafukho Fredrick Muyia , Hinton Barbara E.
Published: September 2003

One major issue in human resource development (HRD) is to determine factors that predict the
performance of employees. The primary purpose of this study was to determine how level of education, training, and
the working conditions of matatu (public service vehicle) drivers determined their job
performance in terms of reduced road traffic accidents. Proportionate and simple random sampling techniques were
employed to select 143 drivers who completed and returned the questionnaires. Multiple regression analysis was
used to test the hypotheses stated. The findings indicate that the variables of driver experience and hours worked
had a significant relationship with the dependent variable rates of traffic accidents per driver as hypothesized.
The variables of education level, training, salary earned, and average speed traveled did not have a significant
relationship with the dependent variable.
Using personality tests in leadership development: Test format effects and the mitigating impact of explanations and feedback
Authors: Harland Lynn K.
Published: September 2003

Organizations using personality tests in management development programs must choose from an array of
personality tests and formats. The most common formats are normative (for example, Likert type) and
forced choice. Although there are some potential advantages to using the forced‐choice format for
development, it is possible that participants may view the forced‐choice format more negatively than the
normative format. Hypothesis 1 proposed that participants would initially view the forced‐choice format as
less accurate, less respectful, less useful, and providing less test taker control. Hypothesis 2 proposed that an
explanation of forced‐choice format benefits would mitigate initial negative reactions. Finally, hypothesis
3 proposed that receiving test feedback would mitigate negative perceptions of forced‐choice format
accuracy and usefulness. The participants, 255 part‐time M.B.A. students in a leadership development
course, were randomly assigned to three experimental conditions: normative, forced choice with an explanation, and
forced choice with no explanation.
The effect of workplace gender and race demographic composition on hiring through employee referrals
Authors: Taber Mary E. , Hendricks Wallace
Published: September 2003

This quantitative study tests whether the gender and race composition of the workplace helps explain why there
are systematic differences in how employees are hired across gender and race. We find evidence that differences
across racial groups in the use of employee referrals may be explained partly by differences in the race
composition of the workplace. We also find evidence that recruiting source models that do not include workplace
demographic composition may misestimate the effect of the new employee's race on the hiring source.
Gender‐based approach to the understanding of leadership roles among retail managers
Authors: Kim Hye‐Shin , Shim Soyeon
Published: September 2003

Using survey data (n = 205) obtained from retail managers and executives of national retail
chain store companies, we sought to identify the effect of gender on leadership roles in conjunction with
personal
values, job characteristics, and other personal values. Quinn's theoretical model of competing leadership
roles
(1984, 1988) was used as a conceptual framework. Results indicated that the members of the female
group
perceived themselves to display a higher level of mentor and broker roles than did the members of the male
group.
Further analysis indicated that certain personal values such as social affiliation and growth and development
predicted the mentor and broker roles, respectively, without diminishing the effect of gender. Finally,
perceived
job characteristics (that is, feedback) also predicted the broker role. Theoretical and managerial
implications are discussed.
Shaping the future: Writing up the method on qualitative studies
Authors: Rocco Tonette S.
Published: September 2003

As the qualitative method editor for HRDQ, I report my observations on qualitative
manuscripts to the editorial board at the annual Academy of Human Resource Development meeting. The problem
areas identified in the manuscripts reviewed are organization and format, the relationship of the conceptual
and method, the method (type of study, conceptual framework, sample, data collection, data analysis,
integrity measures, and data management), and discussion and data presentation. Here, I share the portion
of the report on method and data presentation with novice researchers in an effort to improve submissions.
Transformational learning in leadership and management positions
Authors: Elkins Samuel L.
Published: September 2003

This article summarizes the research and criticisms regarding transformational learning and how it might be
adapted as a competency trait in the area of management and leadership development. In addition, it explores
areas where research is lacking regarding transformational learning for individual development and suggests
methods to operationalize transformational learning competencies.
Scrounging for Resources: Reflections on the Whys and Wherefores of Higher Education Finance
Authors: Cantor Nancy , Courant Paul N.
Published: September 2003

Multifaceted fiscal challenges are being placed on public universities, and some possible solutions for the future are offered in this chapter.
Comparative Study of State Tax Effort and the Role of Federal Government Policy in Shaping Revenue Relience Patterns
Authors: King Alexander F.
Published: September 2003

The findings of a study raise many concerns regarding state and federal funding strategies and fiscal inequalities that exist in higher education in the United States.
Weathering the Storm: Generating Revenues for Higher Education During a Recession
Authors: Toutkoushian Robert K.
Published: September 2003

How college and university revenue and expenditure patterns have been affected by the current economic recession is analyzed.
Effects of State Postsecondary Education Structures on Public University Prices and Spending
Authors: Lowry Robert C.
Published: September 2003

Public universities located in states with systems that enhance political control and universities whose trustees are selected by nonacademic stakeholders charge significantly lower prices than universities located in states with decentralized systems and those whose trustees are selected by academic stakeholders.
Determining the Costs of Transfer Students at American Colleges and Universities
Authors: Cheslock John J.
Published: September 2003

This chapter seeks to improve our understanding of the determinants and cost of an institution's transfer student enrollment.
Sources and Uses of Annual Giving at Private Research Universities
Authors: Smith Christopher L. , Ehrenberg Ronald G.
Published: September 2003

This chapter discusses why private research universities differ in the sources and uses of their annual giving.
Is There a Dark Side to Endowment Growth?
Authors: Oster Sharon M.
Published: September 2003

When the effect of endowment growth on the behavior of university and college donors is explored, some evidence of donor adverse reactions to endowment growth is found, particularly among certain classes of donors.
Morphometric relationships of take‐off speed in anuran amphibians
Authors: Choi Inho , Shim Jae Han , Ricklefs Robert E.
Published: September 2003

Locomotory speed correlates with muscle mass (determining force and stride rate), limb length (stride rate and distance), and laterally compressed body trunk (force and stride distance). To delineate generalization of the locomotory‐morphometric relationships specifically in anuran amphibians, we investigated take‐off speed and the three morphological variables from seven species, Rana nigromaculata, R. rugosa, and Bombina orientalis, Eleuthrodectilus fitzingeri, E. diastema, Bufo typhonius, Colostethus flotator and Physalaemus pustulosus. The fastest jumper E. fitzingeri (3.41 m s−1) showed 2.49‐fold greater speed than the slowest B. typhonius. Take‐off speed correlated well with both thigh muscle mass relative to body mass and hindlimb length relative to snout‐vent length (HL/SVL), but poorly correlated with the inter‐ilial width relative to SVL. The best morphological predictor was HL/SVL (speed=−3.28+3.916 HL/SVL, r=0.968, P<0.0001), suggesting that anuran take‐off speed is portrayed well with high gear and acceleration distance characterized by hindlimbs. J. Exp. Zool. 299A:99–102, 2003. © 2003 Wiley‐Liss, Inc.
Fecal Corticosterone Assessment in the Epaulette Shark, Hemiscyllium ocellatum
Authors: Karsten Amanda H. , Turner John W.
Published: September 2003

The present study examined the feasibility of measuring the steroid hormone corticosterone in fecal extracts of epaulette sharks, Hemiscyllium ocellatum. Six immature, captive‐raised epaulette sharks (four females and two males) were obtained from two different zoos and were maintained in a closed‐system, 530–liter aquarium. After a one‐month adaptation, fecal samples were collected daily from each animal for 33 days. Five‐day sets of samples were pooled within animals to insure sufficient material for analysis. Fecal hormone extraction was achieved using repeated cycles of dichloromethane and aqueous washes. The levels of corticosterone were measured by reverse‐phase high‐performance liquid chromatography (HPLC). Corticosterone presence in HPLC eluent peaks from fecal extracts was determined by comparison of the elution pattern of corticosterone standard with the elution patterns of fecal extracts with and without the addition of tritiated corticosterone or exogenous, unlabeled corticosterone. Exclusive presence of corticosterone in HPLC eluent peaks presumed to be corticosterone was determined by nuclear magnetic resonance mass spectrometry. Corticosterone levels, calculated from a 10–point standard curve, ranged from 1.2 to 20.9 ng/g feces across all sharks, with 92.3% of values being ≤13.5 ng/g. Within individuals, the lowest average for corticosterone levels across 33 days was 2.6±0.4 ng/g feces, and the highest average was 8.4±2.2 ng/g feces. This study demonstrated that corticosterone was extractable from and reliably measurable in fecal extracts of epaulette sharks. This is the first evidence of this hormone in epaulette sharks and the first report of fecal corticosterone in elasmobranchs. J. Exp. Zool. 299A:188–196, 2003. © 2003 Wiley‐Liss, Inc.
Finiteness of U‐rank implies simplicity in homogeneous structures
Authors: Hyttinen Tapani
Published: September 2003

A (large) superstable homogeneous structure is said to be simple if every complete type over any set A has a free extension over any B ⊇ A. In this paper we give a characterization for this property in terms of U‐rank. As a corollary we get that if the structure has finite U‐rank, then it is simple. (© 2003 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On the complexity of categoricity in computable structures
Authors: White Walker M.
Published: September 2003

We investigate the computational complexity the class of Γ‐categorical computable structures. We show that hyperarithmetic categoricity is Π11‐complete, while computable categoricity is Π04‐hard. (© 2003 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Polycarbonate Crystallization by Vapor‐Grown Carbon Fiber with and without Magnetic Field
Authors: Takahashi Tatsuhiro , Yonetake Koichiro , Koyama Kiyohito , Kikuchi Tokio
Published: September 2003

Polycarbonate (PC)/vapor‐grown carbon fiber (VGCF™) composite was prepared through melt compounding. It was unexpectedly found from differential scanning calorimetry (DSC) and wide angle X‐ray diffraction (WAXD) that the crystallization of PC was substantially accelerated in the presence of the ordered graphite surface of VGCF™. To make an aligned structure of PC crystallization together with the orientation of VGCF™, a magnetic field of 2.4 T was applied to the composite under several temperature profiles. The WAXD pattern revealed that not only dispersed VGCF™ but also matrix PC crystallization was magnetically aligned through the optimization of processes. The evidence for PC crystallization by VGCF™ with and without magnetic force is described.

Optical micrograph (a) and WAXD pattern (b) of PC/VGCF™ (95:5 wt. ratio) composite which was treated under a magnetic field (vertical direction) of 2.4 T under an optimized heating profile.

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Optical micrograph (a) and WAXD pattern (b) of PC/VGCF™ (95:5 wt. ratio) composite which was treated under a magnetic field (vertical direction) of 2.4 T under an optimized heating profile.
Polymerization of Norbornene with CoCl2 and Pyridine Bisimine Cobalt(II) Complexes Activated with MAO
Authors: Pelascini Frédéric , Peruch Frédéric , Lutz Pierre J. , Wesolek Marcel , Kress Jacky
Published: September 2003

Addition polymerization of norbornene was performed with several pyridine bis(imine) cobalt dichloride complexes activated with methylaluminoxane (MAO), first described for ethylene polymerization. For the first time, norbornene was also polymerized with CoCl2 associated to MAO. The influence of several reaction parameters has been investigated. Quite different behavior was observed compared with ethylene polymerization. Moreover, the copolymerization of ethylene and norbornene with these complexes was not possible but led to a mixture of both homopolymers.

The pyridine bis(imine) cobalt dichloride complexes used in this study.

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The pyridine bis(imine) cobalt dichloride complexes used in this study.
Transparent Nonlinear Optical Polymers for All‐Optical Wavelength Converters in Optical Fiber Communications
Authors: Park Seung Koo , Do Jung Yun , Ju Jung‐Jin , Park Suntak , Kim Min‐su , Lee Myung‐Hyun
Published: September 2003

After synthesizing two chromophores with imine, we prepared acrylic nonlinear optical (NLO) polymers that contained the chromophores for all‐optical wavelength converters in optical fiber communication. The polymers show high d33, 35 pm · V−1, at 1.55 μm (pumping beam), considering their low losses, −3.0 dB · cm−1, at a wavelength of 0.785 μm (near second harmonic signal beam of the pumping beam). This result means that the polymers are good candidates for wavelength converters of an approximately 1.55 μm signal beam.

UV‐vis spectra of NLO chromophores and polymers.

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UV‐vis spectra of NLO chromophores and polymers.
Determination of Propagation Rate Coefficient of Acrylates by Pulsed‐Laser Polymerization in the Presence of Intramolecular Chain Transfer to Polymer
Authors: Nikitin Anatoly N. , Castignolles Patrice , Charleux Bernadette , Vairon Jean‐Pierre
Published: September 2003

Unusual difficulties are faced in the determination of propagation rate coefficients (kp) of alkyl acrylates by pulsed‐laser polymerization (PLP). When the backbiting is the predominant chain transfer event, the apparent kp of acrylates determined in PLP experiments for different frequencies should range between kp (propagation rate coefficient of the secondary radicals) at high frequency and k at low frequency. The k value could be expressed from kinetic parameters: $k_{\rm p}^{{\rm av}} = k_{\rm p} - {{k_{\rm p} - k_{{\rm p}2} } \over {1 + {{k_{{\rm p}2} [{\rm M}]} \over {k_{{\rm fp}} }}}}$, where kfp is the backbiting rate coefficient, kp2 is the propagation rate coefficient of mid‐chain radicals, and [M] is the monomer concentration.

Apparent propagation rate coefficients determined for different frequencies by simulating the PLP of n‐butyl acrylate at 20 °C. Horizontal full lines show the values of kp and k.

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Apparent propagation rate coefficients determined for different frequencies by simulating the PLP of n‐butyl acrylate at 20 °C. Horizontal full lines show the values of kp and k.
Parallel Breakup of Polymer Drops under Simple Shear
Authors: Lin Bin , Mighri Frej , Huneault Michel A. , Sundararaj Uttandaraman
Published: September 2003

The deformation and breakup of a single polycarbonate drop in a polyethylene matrix is studied at high temperatures under simple shear flow using a transparent Couette device. We observed “parallel breakup” where the drop breaks after being stretched into a thin sheet parallel to the flow. The breakup occurs at a viscosity ratio greater than 3.5. Deborah number and a stress ratio incorporating elastic moduli can characterize the “parallel breakup”.

Deformation and breakup of a polycarbonate drop in a polyethylene matrix.

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Deformation and breakup of a polycarbonate drop in a polyethylene matrix.
Formation of Giant Needle‐Like Polycation‐Bile Acid Complexes
Authors: Kaneko Tatsuo , Ichikawa Ayako , Gong Jian Ping , Osada Yoshihito
Published: September 2003

The complexation of bile acids with various solvated polycations was studied. A one‐to‐one complex was precipitated when an aqueous solution of cholic acid sodium salt (CA) was mixed with aqueous solutions of 3,3‐ionene and grew to form crystals with needle‐like morphology, 3 millimeters in length. Hydrogen bonding of hydroxyls at the steroid face and the spacing between cationic sites of polycations were crucial for the formation of the giant needle.

Crossed polarizing microscopic photograph of the complex composed of cholic acid sodium salt and 3,3‐ionene.

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Crossed polarizing microscopic photograph of the complex composed of cholic acid sodium salt and 3,3‐ionene.
Packing Studies on Poly(di‐n‐alkylsilylenemethylene)s
Authors: Park Soo‐Young , Interrante Leonard V. , Farmer B. L.
Published: September 2003

The packing of poly(di‐n‐alkylsilylenemethylene) (PDASMs) chains was studied by using X‐ray, electron diffraction, and molecular modeling methods. X‐ray and electron diffraction measurements revealed unit cells in which the PDASMs were efficiently packed. The PDASM with the longer alkyl side chains, such as poly(di‐n‐propylsilylenemethylene) (PDPrSM), showed packing with the alkyl side chains interlocked with each other like cross‐shaped gears in the two‐dimensional monoclinic unit cell. The PDASM with the shorter ethyl substituent, poly(di‐n‐ethylsilylenemethylene) (PDESM), showed a lack of ability to interlock its side chains due to the short length of the alkyl groups. In these studies, we found that the length of the alkyl side chains could change the packing arrangement of PDASMs from monoclinic to orthorhombic to hexagonal with only short‐range order as the alkyl side chain length decreases at room temperature.

The ab projection of a 4 × 4 chain array of poly(di‐n‐propylsilylenemethylene) (PDPSM) in the monoclinic unit cell.

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The ab projection of a 4 × 4 chain array of poly(di‐n‐propylsilylenemethylene) (PDPSM) in the monoclinic unit cell.
Mathematical analysis of the quasilinear effects in a hyperbolic model blood flow through compliant axi‐symmetric vessels
Authors: Čanić Sunčica , Kim Eun Heui
Published: September 2003

In this paper, we present a mathematical analysis of the quasilinear effects arising in a hyperbolic system of partial differential equations modelling blood flow through large compliant vessels. The equations are derived using asymptotic reduction of the incompressible Navier–Stokes equations in narrow, long channels.

To guarantee strict hyperbolicity we first derive the estimates on the initial and boundary data which imply strict hyperbolicity in the region of smooth flow. We then prove a general theorem which provides conditions under which an initial–boundary value problem for a quasilinear hyperbolic system admits a smooth solution. Using this result we show that pulsatile flow boundary data always give rise to shock formation (high gradients in the velocity and inner vessel radius). We estimate the time and the location of the first shock formation and show that in a healthy individual, shocks form well outside the physiologically interesting region (2.8m downstream from the inlet boundary). In the end we present a study of the influence of vessel tapering on shock formation. We obtain a surprising result: vessel tapering postpones shock formation. We provide an explanation for why this is the case. Copyright © 2003 John Wiley & Sons, Ltd.