Argyle Communicating by Telephone

1. Auflage 2013
ISBN: 978-1-4832-8628-0
Verlag: Elsevier Science & Techn.
Format: PDF
Kopierschutz: 1 - PDF Watermark

E-Book, Englisch, Band Volume 15, 187 Seiten, Web PDF

Reihe: International Series in Experimental Social Psychology

This book examines the contribution which social psychology has made to telecommunications, and in turn considers how telecommunications have contributed to social psychology. The emphasis throughout is on experimental research and theory. The history and development of the telephone is discussed, with particular attention paid to its uses and effectiveness, especially in interviewing and surveys, crisis intervention and counselling, and conferences and teaching. The theoretical background to the main arguments of the book are introduced, concentrating on non-verbal communication, especially looking, eye-contact, seeing and cuelessness. Outcome research, in particular the transmission of information and problem solving, persuasion and person perception is discussed. Process is also explored, including the content and style of interactions. The concluding section examines recent research on teaching and learning by telephone.

Autoren/Hrsg.

Argyle, Michael

Inhaltsverzeichnis

1;Front Cover;1
2;Advances in Heterocyclic Chemistry, Volume 68;4
3;Copyright Page;5
4;Contents;6
5;Contributors;10
6;Preface;12
7;Chapter 1. Acyclonucleosides: Part 2. diseco-Nucleosides;14
7.1;III. diseco-Nucleosides from Two Bond Disconnections;14
7.2;References;94
8;Chapter 2. 1,3,2-Dioxathiolane Oxides: Epoxide Equivalents and Versatile Synthons;102
8.1;I. Introduction;103
8.2;II. Nomenclature;103
8.3;III. Theoretical Aspects;104
8.4;IV. Thermodynamic Aspects;106
8.5;V. Experimental Structural Methods;107
8.6;VI. Structure Analysis;117
8.7;VII. Synthesis of Cyclic Sulfites and Cyclic Sulfates;119
8.8;VIII. Reactivity;136
8.9;IX. Reaction with Radicals;178
8.10;X. Electrochemical Reduction of Cyclic Sulfates;179
8.11;XI. Application in Research and Industry;180
8.12;XII. Biological Activities;181
8.13;XIII. Conclusion;182
8.14;References;182
9;Chapter 3. Methylpyridines and Other Methylazines as Precursors to Bicycles and Polycycles;194
9.1;I. Introduction;195
9.2;II. Methyl and Alkyl;196
9.3;III. Methyl and Imine;198
9.4;IV. Methyl and Cyano;199
9.5;V. Methyl and Carbonyl;202
9.6;VI. Methyl and Amino;210
9.7;VII. Methyl and N-Acylamino;214
9.8;VIII. Methyl and Imino;216
9.9;IX. Methyl and Azo;216
9.10;X. Methyl and Nitro;217
9.11;XI. Methyl and Thiol;219
9.12;XII. Methyl and Ring Carbon;219
9.13;XIII. Methyl and Ring Nitrogen;223
9.14;XIV. Miscellaneous;230
9.15;References;230
10;Chapter 4. The Chemistry of C-Nucleosides and Their Analogs I: C-Nucleosides of Hetero Monocyclic Bases;236
10.1;I. Introduction;238
10.2;II. Definitions of Analogs;242
10.3;III. General Methods of Synthesis;243
10.4;IV. Azirine C-Nucleosides;243
10.5;V. Diazirine C-Nucleosides;245
10.6;VI. Azole C-Nucleosides;246
10.7;VII. 1,2-Diazole C-Nucleosides;272
10.8;VIII. 1,3-Diazole C-Nucleosides;290
10.9;IX. 1,2-Oxazole C-Nucleosides;302
10.10;X. 1,3-Oxazole C-Nucleosides;310
10.11;XI. 1,2-Thiazole C-Nucleosides;318
10.12;XII. 1,3-Thiazole and 1,3-Selenazole C-Nucleosides;319
10.13;XIII. 1,2,3-Triazole C-Nucleosides;331
10.14;XIV. 1,2,4-Triazole C-Nucleosides;337
10.15;XV. 1,2,3-Oxadiazole C-Nucleosides;341
10.16;XVI. 1,2,4-Oxadiazole C-Nucleosides;342
10.17;XVII. 1,2,5-Oxadiazole C-Nucleosides;343
10.18;XVIII. 1,3,4-Oxadiazole C-Nucleosides;344
10.19;XIX. 1,2,4-Thiadiazole C-Nucleosides;347
10.20;XX. 1,3,4-Thiadiazole C-Nucleosides;348
10.21;XXI. 1,3,4-Oxathiazole C-Nucleosides;351
10.22;XXII. Tetrazole C-Nucleosides;352
10.23;XXIII. Azine C-Nucleosides;354
10.24;XXIV. 1,2-Diazine C-Nucleosides;367
10.25;XXV. 1,3-Diazine C-Nucleosides;370
10.26;XXVI. 1,4-Diazine C-Nucleosides;392
10.27;XXVII. 1,2-Oxazine C-Nucleosides;397
10.28;XXVIII. 1,3-Oxazine C-Nucleosides;398
10.29;XXIX. 1,3-Thiazine C-Nucleosides;402
10.30;XXX. 1,2,4-Triazine C-Nucleosides;403
10.31;XXXI. 1,3,5-Triazine C-Nucleosides;407
10.32;XXXII. 1,2,4,5-Tetrazine C-Nucleosides;407
10.33;References;408

Leseproben

Acyclonucleosides: Part 2. diseco-Nucleosides*

E.S.H. El Ashry; Y. El Kilany    Chemistry Department, Faculty of Science, Alexandria University, Alexandria, Egypt

Abstract

This chapter is the second of a sequence of three chapters that appears in successive volumes of this series dealing with the chemistry of acyclonucleosides. The first chapter appeared in the previous volume [97AHC391] and dealt with seco-nucleosides (one bond disconnection). This chapter deals with diseco-nucleosides (two bond disconnections). The final chapter of this series will deal with tri-, tetra-, and pentaseco-nucleosides, as well as contain an appendix of the literature that appeared after the three chapters were prepared.

III diseco-Nucleosides from Two Bond Disconnections

Acyclonucleosides that are considered under this type of disconnection are those resulting from omitting any two bonds from the pentose. There are seven such types.

A 1',2'- and 2',3'-diseco-Nucleosides (Type 2.1)

The most important member is the guanine analog. There are various modifications under this type of acyclic nucleoside.

1 General Methods for Construction

Most of these methods involve the alkylation of the heterocyclic ring by a suitable alkoxy alkyl halide. Further modification on the heterocyclic rings may sometimes be used on a preformed acyclonucleoside. Thus, the chloromethyl ether 266 was prepared from epichlorohydrin (264) by treatment with benzyl alcohol and aqueous NaOH to give 1,3-di-O-benzylglycerol 265 (83JMC759). Alternatively, 265 was prepared from 1,3-dichloro-2-hydroxypropane 268 (84CJC241). Chloromethylation of 265 gave 266, whose treatment with potassium acetate gave 2-O-(acetoxymethyl)-1, 3-di-O-benzylglycerol (267) (83JMC759). The choice of the hydroxy protecting groups must be made to avoid difficulties encountered with the removal of the benzyl groups during the subsequent steps, particularly in the cytosine series. Thus, the requisite acyclic chain 272 was prepared by commencing with 1,3-dichloro-2-propanol 268. Methoxymethylation of 268 gave 269, where this group served a dual purpose. It protected that position from a trans-acylation process in the subsequent step and furnished the backbone methyleneoxy unit whose methoxy group could be converted into the most suitable leaving group. Treatment of 269 with the desired acid salt in DMF gave 270, whose acetolysis gave 271, which converted it to the bromomethylester 272 (88JMC144).

The synthesis was started by condensing the persilylated base with chloromethylether 266 (79JMC21; 82CJC3005; 84CJC16; 85JMC358, 85JMC971, 85USP4508898; 87MI4; 88MI2; 89MI8; 90GEP3906357). Both mercuric cyanide and tetra-n-butylammonium iodide (TBAI) were frequently used as catalysts in the coupling reactions. The latter catalyst has the advantages that it is less toxic, is required in smaller quantities, and involves reactions that are generally easier to manipulate during workup. Lithium bromide/ TFA/MeCN was also used (88MI2). In the case of triazine derivatives, in addition to the major product, a minor quantity of the 4-alkylated isomer was obtained (91MI5). Direct or phase catalytic, hydrogenation of 273 gave 274, except in the presence of a halogen or nitro group when boron trichloride was used (84CJC16,84CJC241; 85JMC358,85JMC971; 87MI2; 93MI1). Attempted debenzylation with BBr3 gave a 2-methoxymethyl derivative because of complex formation between BBr3 and the C-2 oxygen. Nucleophilic substitution may have occurred at C-1' (N — CH2 — O) when the complex was quenched by the addition of MeOH (91MI5). However, the chlorine atom in position 6 of 6-chloro-Pu and 6-chloro-Gu could be hydrogenolyzed without any significant loss of the benzyl groups (84-CJC241).

In the case of purine derivatives, the N-7 isomers were obtained, in addition to the N-9 isomers; the N-7 isomers rearranged to the N-9 on heating (84CJC2702). The 6-chloropurines could be converted to the corresponding methoxy or hydroxy derivatives by NaOH/MeOH/H2O at room temperature and on heating, respectively. The 2-amino-6-chloropurines were converted to the 2-amino-6-methoxypurines and to the guanine analogs by reaction with NaOMe and NaOH/MeOH/H2O, respectively (84CJC2702). In 2,6-dichloropurine, substitution of the 6-chlorine atom takes place preferentially, by which means another substituent can be introduced later at the 2-position [86IJC(B)823].

Scheme 55

The synthesis of chiral acyclic nucleosides 276 utilizes the readily available protected acetoxymethyl ether of glycerol 275, which reacted with silylated nucleobases under phase transfer conditions using dibenzo-18-crown-6 to give N-9 purinyl and N-1 pyrimidinyl acyclonucleosides. Removal of the benzoyl groups by methanolic ammonia gave 277 (88JMC144; 89TL6165).

The bis-chloromethyl ether 280 could also be used for alkylation. Thus, isopropylidenation of glycerol (278) followed by benzoylation and deisopropylidenation gave 279, whose chloromethylation gave 280. Coupling of the latter with silyl derivatives of bases gave 281, whose deprotection gave 282, whereas the use of sodium hydroxide led to a cleavage of one of the methyl ether linkages to give 283 and 284. The former belongs to nucleoside analogs of type 2.2. Mixed derivatives of 282 were also prepared (86MI2).

Another preparation of analogs 287 was by reacting the purine bases with acetal 286 prepared from 285 (92GEP4020481).

The synthesis could be achieved via a transpurination process by reaction of tetraacetylguanosine 288 with the acetoxymethyl ether 271 using chlorobenzene as a solvent, or with 2-(acetoxymethoxy)-1,3-dibenzyloxypropane (267) by fusion to give a separable 9- and 7-isomeric mixture of 289 and 290 (82BBR1716; 89MI5). Heating 290 gave a mixture of 290 and 289. The reaction of 267 with diacetylguanine gave a similar mixture (83JMC759). The tetraacetyladenosine did not undergo such a transpurination process.

2 Modification on the Heterocyclic Rings

Some modifications on the heterocyclic rings are shown in Scheme 56, in particular the use of 6-chloropurine in coupling reactions, followed by substitution of the chlorine by an amino group. Moreover, the preferential substitution of one of the chlorine atoms in 2,6-dichloropurines introduces two different substituents at these two positions.

Scheme 56

Scheme 57

Scheme 58

Because of the susceptibility of cytidine derivatives to overreduction on hydrogenolysis of the benzyl ether groups, acyclic analogs were prepared from the uridine analogs by acetylation (Ac2O/Py) to give 291; P4S10 treatment gave 294, whose reaction with NH3/MeOH gave 296. In contrast, the fluorocytidine 297 was prepared from 292 via 295 by phosphorodichloridate and triazole followed by ammonia. Bromination (Br2/Ac2O/AcOH) of 291 gave 293, which could be deacetylated with NH3/MeOH (85JMC358).

The synthesis of the 5-allyl and 5-n-propyl derivatives used organopalladium intermediates. The uracil derivative 299 first was treated with mercuric acetate, then was condensed with allyl chloride in the presence of Li2PdCl4 to give the 5-allyl derivatives 300 whose reduction gave 301. Treatment of 298 with iodine monochloride led to the 5-iodo derivative 302. Compound 302 also served as the starting point for the introduction of the bromovinyl side chain at C-5 by the conversion of the 5-iodo to the 5-methyl propenoate 303. The ester groups in 303 were hydrolyzed, and the bromine atom was introduced using N-bromosuccinimide to give 304 (84CJC16). None of the compounds tested showed significant activity.

Scheme 59

Scheme 60

Scheme 61

Coupling base 305 with 266 gave...