Special Issue

Alan R. Katritzky's Special Issues, Vol. 37, No. 1, 1994

59 data found. 31 - 59 listedFirst Previous
Paper | Special issue | Vol 37, No. 1, 1994, pp. 293 - 301
Published online:
DOI: 10.3987/COM-93-S1
Cyclization with Nitrenium Ions Generated from N-Methoxy- or N-Allyloxy-N-chloroamides with Anhydrous Zinc Acetate. Synthesys of N-Hydroxy- and N-Methoxynitrogen Heterocyclic Compounds

Yasuo Kikugawa,* Masahiro Shimada, and Kazuhiro Matsumoto

*Faculty of Pharmaceutical Sciences, Josai University, 1-1 Keyakidai, Sakado, Saitama 350-0295, Japana


Electrophilic intramolecular aromatic substitution with an N-methoxy- or an N-allyloxyacylnitrenium ion, generated by treatment of an N-methoxy- or an N-allyloxy-N-chloroamide with anhydrous zinc acetate in nitromethane, leads to formation of a nitrogen heterocyclic compound bearing an N-methoxy- or N-allyloxy group. The latter is readily converted to the corresponding N-hydroxy compound by palladium-catalyzed removal of the allyl group.

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Paper | Special issue | Vol 37, No. 1, 1994, pp. 303 - 309
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DOI: 10.3987/COM-93-S2
Studies on the Site-selective N-Acyliminium Ion Cyclization: Synthesis of (±)-Glochidine and (±)-Glochidecine

Yong Sup Lee, Sung Hwan Kim, Sun Ho Jung, Sook Ja Lee, and Ho-Koon Park*

*Organic Chemistry Laboratory, Korea Institute of Science and Technology, P.O. Box 131, Cheongryang, Seoul 130-650, Korea


Studies on the N-acyliminium ion cyclization of hydroxylactams bearing both carbon and nitrogen nucleophile in the same molecule are described. The site selection in the cyclization of hydroxylactam could be controlled by the absence or presence of acid catalyst to afford (±)-glochidine and (±)-glochidicine.

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Paper | Special issue | Vol 37, No. 1, 1994, pp. 311 - 321
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DOI: 10.3987/COM-93-S5
1-Alkoxymethyl- and 1-Alkylthiomethyl-4-dimethylaminopyridinium Chlorides

Pernak Juliusz* and Michalak Lucyna

*Poznan Technical University, Institute of Chemical Technology and Engineering, pl.Sklodowskiej-Curie 2, 60-965 Poznan, Poland


ROCH2Cl or RSCH2Cl reacts with DMAP to form stable pyridinium chlorides. Reaction of these chlorides with NaOH produces the corresponding 4-pyridones. N-Alkoxymethylation of a free NH group of azoles is developed from 1-alkoxymethyl-4-dimethylaminopyridinium intermediates.

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Paper | Special issue | Vol 37, No. 1, 1994, pp. 323 - 329
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DOI: 10.3987/COM-93-S8
Synthesis of Some Novel Naphthoquinone Fused Selenazoles and 2-Amino-3-alkylseleno-1,4-naphthoquinones

Ming-De Ruan,* Zheng-Jie Wu, Wei-Qiang Fan,* Xun-Jun Zhou, and Rong-Shen Ma

*Department of Chemistry, Hangzhou University, Zhejiang, China 310028, China


A variety of 2-aryl-4,9-dioxonaphtho[2,3-d]selenazoles (4) are prepared from reactions of appropriate aromatic aldehydes and 2-amino-3-seleno-1,4-naphthoquinone sodium salt (3), which is prepared from 2-amino-3-chloronaphthoquinone (2), sodium and selenium powder without isolation. The intermediate (3) reacts with a range of alkyl halides to give 2-amino-3-alkylseleno-1,4-naphthoquinones (5).

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Paper | Special issue | Vol 37, No. 1, 1994, pp. 331 - 345
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DOI: 10.3987/COM-93-S9
On the Bromination of the Three Isomeric Thieo[c]fused 1,5-Naphthyridines and Their 5-N-Oxides

Johan Malm, Anna-Britta Hörnfeldt, and Salo Gronowitz*

*Organic Chemistry 1 Chemical Center, University of Lund, P. O. Box 124, S-221 00, Lund, Sweden


Thieno[3,4-c]-1,5-naphthyridine (1) and its 5-N-oxide (5) were conveniently brominated at room temperature with tetrabutylammonium perbromide in the presence of a large excess of sodium hydrogen carbonate. Compound (1) gave the 1- and 3-bromo derivatives in a 4:1 ratio, while 5 was regioselectively brominated in the 3-position. Thieno[2,3-c]-1,5-naphthyridine (7), its 5-N-oxide (11) and thieno[3,2-c]-1,5-naphthyridine (14) did not react under these conditions, but gave products in the reaction with bromine in refluxing thionyl chloride. Compound (7) gave the 1-brow derivative as main product and interestingly the 1,7-dibromo derivative as by-product. The reaction of 11 and 14 with bromine in thionyl chloride gave mainly chlorinated products.

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Paper | Special issue | Vol 37, No. 1, 1994, pp. 347 - 354
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DOI: 10.3987/COM-93-S10
Synthesis and Conformation of 3-Nitro-2-[1-(L)-prolyl]thiophene Derivatives

Kondam Venodhar Reddy and Srinivasachari Rajappa*

*Division of Organic Chemistry (Synthesis), National Chemical Laboratory, Pune 411 008, India


Chiral thiophene derivatives with a strong push - pull system (nitroenamine) have been synthesized and their solution conformation has been determined.

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Paper | Special issue | Vol 37, No. 1, 1994, pp. 355 - 366
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DOI: 10.3987/COM-93-S14
Studies towards 3,4-Dimethoxy-1-methyl-1,2-dihydropyridine, So-called Arecolidine, or Its Tautomers

Eckehard V. Dehmlow* and Ralf Westerheide

*Fakultät für Chemie, Universität Bielefeld, D33615 Bielefeld, Germany


Different synthetic paths towards the title compound (2) lead to intermediates (3, 11, 13, 14, 15, and 17). All of these, but especially 3 and 14 are very close to the target molecule or its tautomers. These, however, turn out to be too unstable for isolation. Thus, the structure of the compound described as arecolidine must be wrong.

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Paper | Special issue | Vol 37, No. 1, 1994, pp. 367 - 377
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DOI: 10.3987/COM-93-S16
Electron Impact Mass Spectra of para-Substituted N-Heteroaryl Benzylamines

Rossella Fioravanti,* Mariangela Biava, Giulio Cesare Porretta, Salvatore Foti, Giuseppe Musumarra,* and Rosaria Saletti

*Dipartimento di Studi e Tecnologia delle Sostanze Biologicamente Attive, Università degli Studi di Roma "La Sapienza", Piazzale Aldo Moro 5, 00185 Roma, Italy


The 70 eV electron impact mass spectra of some para-substituted N-heteroaryl benzylamines, synthesized through the corresponding Schiff bases, are reported. Typical fragmentation patterns are discussed with the aid of mass analyzed ion kinetic energy spectra and exact mass measurements. The compounds are relatively stable under electron impact, the molecular ion being the base peak or the second most intense ion in the spectra. The dominating breakdown process is the benzylic cleavage, that gives rise to the base peak in some of the investigated compounds and to the second intense peak in others.

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Paper | Special issue | Vol 37, No. 1, 1994, pp. 379 - 386
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DOI: 10.3987/COM-93-S18
Aminations with Oxaziridines – Synthesis of Aryl- and Hetarylhydrazines

Siegfried Andreae* and Ernst Schmitz

*Zentrum für Selektive Organisch Synthese, KAI e V., Rudower Chaussee 5, D-12489, Berlin-Adlershof, Germany


Five acetylaminobenzenes (2) (X=CH), two 3-acetylaminopyridines (2) (X=N) and one 3-acetylaminopyridine-1-oxide (2) (X=N(O)) are aminated by 1-oxa-2-azaspiro[2.5]octane (1) / DABCO to cyclohexylidenehydrazino compounds (3), which are characterized as benzaldehyde or 4-nitrobenzaldehydehydrazones (4). In some cases the acetyl group is removed during the amination.

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Paper | Special issue | Vol 37, No. 1, 1994, pp. 387 - 400
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DOI: 10.3987/COM-93-S20
Synthesis of Hybrid Tilivallines and Their 11-Cyano Analogs

Nobuyuki Matsunaga, Toyohiko Aoyama, and Takayuki Shioiri*

*Faculty of Pharmaceutical Sciences, Nagoya City University, Tanabe-dori, Mizuho-ku, Nagoya 467-8603, Japan


Hybrid tilivallines (4), derived from tilivalline (1a) and anthramycin (2) or tomaymycin (3), and their 11-cyano analogs (15) have been efficiently synthesized from the acetal amides (7a, b) : the key step is an intramolecular Mannich type cyclization accompanied with introduction of indole or nitrile function.

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Paper | Special issue | Vol 37, No. 1, 1994, pp. 401 - 411
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DOI: 10.3987/COM-93-S23
Synthesis of 3,4-Dihydropyridazino[1,6-a]benzimidazoles

Mohamed Khodja, Dieter Sicker, and Horst Wilde*

*Institut für Organische Chemie, Universität Leipzig, Johannisallee 29, D-04103 Leipzig, Germany


3,4-Dihydropyridazino[1,6-a]benzimidazoles (4a-e) have been prepared by catalytical hydrogenation of dialkyl (E)-2-(substituted 2-nitrophenylhydrazono) glutarates (1a-e) to the respective amines (2) followed by their base catalyzed cyclization in a tandem reaction proceeding via 4,5-dihydropyridazin-6(1H)-one intermediates (3).

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Paper | Special issue | Vol 37, No. 1, 1994, pp. 413 - 423
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DOI: 10.3987/COM-93-S26
Preparation of Optically Active Tricyclic 1,4-Dioxepin-5-one Derivatives and Its Application to Asymmetric Alkylation

Keisuke Kato, Hiroshi Suemune, and Kiyoshi Sakai*

*Faculty of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan


Chiral hicyclic α,β-unsaturated lactones (6a,b and 8a,b) were easily synthesized from chiral cyclic diols (2-4) and cyclic β-keto esters (1a,b). Alkylation of 8b proceeded in a highly diastereoselective manner to afford a quaternary carbon.

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Paper | Special issue | Vol 37, No. 1, 1994, pp. 425 - 429
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DOI: 10.3987/COM-93-S27
Lead Tetraacetate Oxidation of a Compound that is Simultaneously a 1- and a 2-Aminobenzotriazole

Dong Ok and Harold Hart*

*Department of Chemistry, Michigan State University, East Lansing MI 48824, U.S.A.


Lead tetraacetate oxidation of bis-aminobiazole (8) in the presence of dienone (11) gave dinitrile (12) in good yield. Possible mechanisms are briefly discussed.

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Paper | Special issue | Vol 37, No. 1, 1994, pp. 431 - 439
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DOI: 10.3987/COM-93-S31
Compounds with Bridgehead Nitrogen Part 74. NMR Spectra and Stereochemistry of 1,3,10,10a-Tetrahydro-5H-oxazolo[3,4-b]isoquinoline and 1,5,6,10b-Tetrahydro-3H-oxazolo[4,3-a]isoquinoline

Trevor A. Crabb* and Asmita V. Patel

*Department of Chemistry, University of Potsmouth, Nuffield Centre, St. Michael's Road Portsmouth PO1 2DT, U.K.


Whereas 1,3,10,10a-tetrahydro-5H-oxazolo[3,4-b]isoquinoline adopts an equilibrium in CDCl3 solution at 295 K in which the trans-fused conformation predominates, 1,5,6,10b-tetrahydro-3H-oxazolo[4,3-a]isoquinoline adopts the O-inside cis-fused conformation. This difference in conformational preference has been explained partly in terms of ring-fusion strain.

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Paper | Special issue | Vol 37, No. 1, 1994, pp. 441 - 459
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DOI: 10.3987/COM-93-S32
Generation of the Dihydro-5H-Thiazolo[3,2-a]pyridin-3-one Ring System by Proton Loss from Isothiomünchnones

Albert Padwa* and Zhijia J. Zhang

*Department of Chemistry, Emory University, 1515 Pierce Drive Atlanta, Georgia 30322, U.S.A.


Dihydro-5H-thiazolo[3,2-a]pyridin-3-ones are easily generated by proton loss from isothiomÜnchnones. The closely related tetrahydro-2H-pyrido[2,1-b][1,3]thiazin-4-one ring system was prepared by heating piperidine-2-thione with acryloyl chloride. These cyclic S,N-ketene acetals undergo smooth reaction with different electrophiles in the presence of Lewis acids.

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Paper | Special issue | Vol 37, No. 1, 1994, pp. 461 - 475
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DOI: 10.3987/COM-93-S34
Enantiomerically Pure β-Amino Sulfides amd β-Amino Thiols from Ephedrine

Martin A. Poelert, Robert P. Hof, Nathalie C. M. W. Peper, and Richard M. Kellogg*

*Department of Organic and Molecular, Inorganic Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherland


Ephedrine and pseudoephedrine are converted by means of a Mitsunobu reaction to respectively trans- and cis-aziridines, which can be ringopened at the benzylic center with inversion of configuration by thiols and thiol acids. The trans-aziridine from ephedrine reacts also with H2S in acetone under which conditions the amino thiol is trapped as the thiazolane. The same aziridine also undergoes cycloaddition with CS2.

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Paper | Special issue | Vol 37, No. 1, 1994, pp. 477 - 486
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DOI: 10.3987/COM-93-S37
Isomerism of Cephalosporin Esters; Theoretical and Practical Aspects

Emil Pop,* Marcus E. Brewster, Antonie Dinculescu, Ming-Ju Huang, and Nicholas Bodor

*Pharmos Corporation, 2 Innovation Drive, Alachua, FL 32615, U.S.A.


Attempts to prepare 1,4-dihydropyridine targetor based chemical delivery systems (CDS) for 7-(thiophene-2-acetamido) cephalosporanic acid (cephalotin) (1) are reported. Reaction of 1 with hydroxyethylnicotinamide resulted in a mixture of δ2 and δ3 isomers of the 3-pyridinylcarbonylamino esters of 1; after chromatographic separation the δ3 isomer was N-methylated and the resulting quaternary pyridinium salt was reduced with sodium dithionite to give the CDS. Attempts to attach the dihydropyridine moiety to 1 as an acyloxyalkyl ester failed. Relative stabilities of the δ3 and δ2 isomers of cephalotin acid and methyl ester, as reflected by theoretically (AM1 and PM3) calculated heats of formation (δHf) indicated that kinetic and mechanistic, rather than thermodynamic factors are responsible for the isomerization of the esters.

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Paper | Special issue | Vol 37, No. 1, 1994, pp. 487 - 499
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DOI: 10.3987/COM-93-S38
The Preparation of Thiophene Appended Vinylogous Iminium Salts and Their Application to the Regioselective Synthesis of Thienylpyrimidines and Thienylpyrroles

John T. Gupton,* Fred A. Hicks, Douglas R. Wilkinson, Scott A. Petrich, and James A. Sikorski

*Department of Chemistry, University of Central Florida, Orlando, Florida 32816, U.S.A.


The synthesis of two, vinylogous iminium salts, which contain an appended thiophene group, are described along with their conversion to thiophene substituted pyrimidines and pyrroles.

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Paper | Special issue | Vol 37, No. 1, 1994, pp. 501 - 514
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DOI: 10.3987/COM-93-S39
Synthesis of Pyrimidinyl Triflates and Palladium-catalyzed Coupling with Organotin and Organozic Reagents

Jessie Sandosham and Kjell Undheim*

*Department of Chemistry, University of Oslo, P.O.Box 1033, Blindern, N-0315 Oslo, Norway


Pyrimidinyl triflates have been synthesized from pyrimidinones using triflic anhydride in the presence of triethylamine. The triflates, in the pyrimidine electrophilic positions, are versatile intermediates for substitution reactions. Carbon substituents are readily introduced in any position by Pd-catalyzed coupling reactions between pyrimidinyl triflates and aryl- or alkenyltin or with the corresponding organozinc reagents. Organozinc reagents are generally more reactive in coupling reaction and will effect the introduction of alkyl substituents.

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Paper | Special issue | Vol 37, No. 1, 1994, pp. 515 - 521
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DOI: 10.3987/COM-93-S44
A Short Synthesis of Enantiomerically Pure (+)-Eldanolide and (-)-cis-Whisky Lactone by Samarium Diiodide Promoted Fragmentation of γ-Halo Esters

Toshio Honda,* Shin-ichi Yamane, Koichi Naito, and Yukio Suzuki

*Institute of Medicinal Chemistry, Hoshi University, 2-4-41 Ebara, Shinagawa-ku, Tokyo 142-8501, Japan


A stereoselective synthesis of (+)-eldanolide and (-)-cis-whisky lactone in optically pure forms has been achieved by employing a regioselective fragmentation reaction of the γ-halo esters as a key step.

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Paper | Special issue | Vol 37, No. 1, 1994, pp. 523 - 528
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DOI: 10.3987/COM-93-S46
Oxidation of Dioxopyprroline with m-Chloroperbenzoic Acid: Selective Formation of 2,3-Dioxo-1,4-oxazine

Takehiro Sano,* Kazuko Amano, Masaharu Seki, Hiroyuki Hirota, Jun Toda, Fumiyuki Kiuchi, and Yoshisuke Tsuda

*Showa College of Pharmaceutical Sciences, 3-3165, Higashi-tamagawagakuen, Machida, Tokyo 194-8543, Japan


Treatment of 4-ethoxycarbonyl-5-phenyl-1H-pyrrole-2,3-diones (1a-1e) and 4-benzoyl-1,5-diphenyl-1H-pyrrole-2,3-dione (1f) with m -chloroperbenzoic acid caused Baeyer-Villiger oxidation to give 2,3-dioxo-1,4-oxazines (2a-2f) in moderate yields, respectively. This conversion of the 1H-pyrrole-2,3-dione into the 2,3-dioxo-1,4-oxazine provides the first synthesis of monocyclic 2,3-dioxo-1,4-oxazine ring system.

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Paper | Special issue | Vol 37, No. 1, 1994, pp. 529 - 539
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DOI: 10.3987/COM-93-S49
Asymmetric Synthesis of a Homochiral Δ2-Isoxazoline Amino Acid Derivative

Bernadette M. Kelly-Basetti, Maureen F. Mackay, Suzanne M. Pereira, G. Paul Savage,* and Gregory W. Simpson

*CSIRO, Divisuon of Chemicals & Polymers, Private Bag 10, Rosebank MDC, Clayton Vic. 3169, Austalia


(2R)-4Methylene-2-phenyl-3-propionyloxazolidin-5-one underwent 1,3-dipolar cycloaddition with 2,6-dichlorobenzonitrile oxide to give (5S,7R)-3-(2,6-diphenyI)-7-phenyl-6-propionyl-2,6-diaza-1,8-dioxaspiro[4.4]non-2-en-9-one, a protected isoxazoline amino acid. The reaction proceeded regiospecifically and with high stereoselectivity. The anti addition product predominated. The regiochemistry of addition was determined by nmr and the stereochemistry of addition was determined by X-ray analysis. The transition state energies for syn and anti addition were calculated using the semi-empirical AM1 method in the MOPAC package.

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Paper | Special issue | Vol 37, No. 1, 1994, pp. 541 - 552
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DOI: 10.3987/COM-93-S57
First Preparation, Structural Determination by X-Ray Crystallographic Analysis and MO-Calculations of Dibenzo[bc,fg][1,4]dithiapentalene and Its Selenium Analogs

Takeshi Kimura, Yasuhiro Ishikawa, Yoshihiro Minoshima, and Naomichi Furukawa*

*Department of Chemistry, University of Tsukuba, 1-1-1 Ten-nodai, Tsukuba-shi, Ibaraki, 305-8571, Japan


Dibenzo[bc,fg][1,4]dithiapentalene and its selenium analogs were prepared by thermolysis and photolysis of 1,9-disubstituted dibenzochalcogenophenes. The X-ray crystallographic analysis of dibenzochalcogenapentalenes revealed clearly that they have completely planar forms. PM3 molecular orbital (PM3 MO) calculation of pentalenes was carried out and their highest occupied and lowest unoccupied molecular orbitals (HOMO and LUMO) were determined.

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Paper | Special issue | Vol 37, No. 1, 1994, pp. 553 - 562
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DOI: 10.3987/COM-93-S64
Reduction of Aromatic Nitroalkenes with Baker's Yeast

Mitsuhiro Takeshita,* Sachiko Yoshida, and Yoichiro Kohno

*Tohoku Pharmaceutical University, 4-4-1 Komatsushima, Aoba-ku, Sendai 981-8558, Japan


Aromatic nitroalkenes were reduced chemoselectively with baker’s yeast to give the corresponding nitroalkanes.

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Paper | Special issue | Vol 37, No. 1, 1994, pp. 563 - 570
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DOI: 10.3987/COM-93-S99
Novel Synthesis of Pyrido[3,4-d]pyrimidines, Pyrido[2,3-d]pyrimidines, and Quinazolines via Palladium-catalyzed Oxidative Coupling

Kosaku Hirota,* Hideki Kuki, and Yoshifumi Maki

*Gifu Pharmaceutical University, 6-1 Mitahora-higashi 5-chome, Gifu 502-8585, Japan


Oxidative-coupling of 6-azavinyl(or vinyl)-1,3-dimethyluracil derivatives (1, 5, and 7) with electron-deficient olefins in the presence of palladium acetate led to the formation of the corresponding 6-substituted pyrido[3,4-d]pyrimidines (4), pyrido[2,3-d]pyrimidines (6), and quinazolines (8 and 9), respectively, via an intermediacy of azatriene.

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Review | Special issue | Vol 37, No. 1, 1994, pp. 571 - 584
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DOI: 10.3987/REV-93-SR1
Substituted 1,2,3-Triazolium-1-ylides as 1,3-Dipoles: Synthons for a Range of Azimine and 1,2,3-Triaza Systems

Richard N. Butler* and Donal F. O'Shea

*Chemistry Department, University College Galway, Ireland


The synthetic scope of the 1,2,3-triazolium-1-ylide system as a 1,3-dipole is outlined.

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Review | Special issue | Vol 37, No. 1, 1994, pp. 585 - 601
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DOI: 10.3987/REV-93-SR2
Bicyclic Compounds Structurally Related to Dehydroacetic Acid and Triacetic Acid Lactone

Marcial Moreno-Mañas* and Roser Pleixats

*Department of Chemistry, Universitat Autònoma de Barcelona, Bellaterra. 08193-Barcelona, Spain


The preparation and reactivity of bicyclic compounds derived from dehydroacetic acid and triacetic acid lactone are reviewed.

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Review | Special issue | Vol 37, No. 1, 1994, pp. 603 - 626
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DOI: 10.3987/REV-93-SR3
Further Researches on the Furoclerodanes from Teucrium Species

Franco Piozzi*

*Dipartimento di Chimica Organica, Università di Palermo, Via Archirafi 20 90123 Palermo, Italy


The review updates the advances reported during the last six years on the chemistry of these diterpenoids.

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Review | Special issue | Vol 37, No. 1, 1994, pp. 627 - 659
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DOI: 10.3987/REV-93-SR5
Complexes of Carboxylic Acids with Pyridines and Pyridine N-Oxides

Zofia Dega-Szafran and Miroslaw Szafran*

*Facluty of Chemistry, Adam Mickiewicz University, ul. Grunwaldzka 6, 60-780 Poznán, Poland


A brief survey is given of dielectric, spectroscopic, thermodynamic, colligative and conductivity properties of non-aqueous solutions of carboxylic acid complexes with pyridines and pyridiie N-oxides. Selected problems of solid state are also reviewed. Solvent and isotopic effects, and the problem of localization of the H-bonded proton are stressed.

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59 data found. 31 - 59 listedFirst Previous