The Synthetic Ones

Author: Lionel Roberts
Publisher: Hachette UK
ISBN: 1473203724
Size: 62.52 MB
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The Synthetic Ones from the Author: Lionel Roberts. Is there a Destiny? Does Fate impose a limit? What Barrier stands between man and the creation of life? Since the legendary failure of the ill-fated Frankenstein, man has tried time and time again to pass those limits. He has created androids, clumsy robots of flesh and blood. He has made men of metal and servants of plastic, with wheels for limbs and magnetic tapes for voices. Man has made things by cross breeding the animal kingdom and destroying Nature's intentions...but man has never yet made man. Or has he? Forbisher thought that he had the answer. It wasn't a clumsy Synthetic. It wasn't an Android, or a Robot, it was a real flesh and blood human being. The beautiful woman in his arms was the product of a laboratory experiment, not the result of a natural biological process. But how could he prove it?

2 Substituted 1 3 Dioxan 5 Ones

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2 Substituted 1 3 Dioxan 5 Ones from the Author: . This dissertation deals primarily with synthesis, reactions and synthetic applications of 2-substituted- 1,3-dioxan-5-ones. This class of compounds could be viewed as synthetic equivalents of natures building block--1,3-dihydroxyacetone and could be used in construction of many polyoxygenated natural products. A general, simple, cheap and easy to scale-up synthesis of 2-substituted-1,3dioxan-5-ones was developed. The yields of this three-step procedure, starting form commercially available tris(hydroxymethyl)nitromethane, ranged from 40 to 90%. The exploration of the chemistry of 2-substituted-1,3-dioxan-5-ones was focused on carboanion chemistry of these compounds. 2-Substituted-1,3-dioxan-5-ones were shown to easily form corresponding lithium, boron and titanium enolates. The 2-'tert'-butyl-2-methyl-1,3-dioxan-5-one was deprotonated enantioselectively in 90% e.e. with the aid of chiral lithium amide derived from (R)- or (S)-'N'-(2,2,2-trifluoroethyl)-1-phenylethylamine. This successful outcome was a result of extensive methodological studies. The enolates reacted readily with electrophiles: reactions with aldehydes provided 'anti' aldols in modest to high selectivities in cases of lithium and boron enolates and 'syn' aldols in case of titanium enolate. The enolates could be conveniently trapped as trimethylsilyl enol ethers or as enol acetates, however they failed to react with alkylating agents. The problem was solved using Enders' chiral hydrazone method. The synthetic utility of 2-substituted-1,3-dioxan-5-ones was illustrated in syntheses of (+)-frontalin and several protected ketohexoses. Additionally, the kinetics of deprotonation of a simple ketone with lithium diisopropylamide was investigated in order to shed some light on the mechanism of this type of reaction. The reaction was shown to be first order in ketone and half order in the base, and half order in the base, which suggests a monomer-based mechanism.

Unified Science

Author: B.F. McGuinness
Publisher: Springer Science & Business Media
ISBN: 9400938659
Size: 73.14 MB
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Unified Science from the Author: B.F. McGuinness. a priori, and what is more, to a rejection based ultimately on a posteriori findings; in other words, the "pure" science of nature in Kant's sense of the term had proved to be, not only not pure, but even false. As for logic and mathematics, the decisive works of Frege, Russell, and White head suggested two conclusions: first, that it was possible to construct mathematics on the basis of logic (logicism), and secondly, that logical propositions had an irrevocably analytic status. But within the frame work of logicism, the status of logical propositions is passed on to mathematical ones, and mathematical propositions are therefore also conceived of as analytic. All this creates a situation where the existential presupposition contained in the Kantian question about the possibility of judgements that are both synthetic and a priori must, it seems, be rejected as false. But to drop this presupposition is, at the same time, to strike at the very core of Kant's programme of putting the natural sciences on a philosophical foundation. The failure of the modern attempt to do so suggests at the same time a reversal of the relationship between philosophy and the individual sciences: it is not the task of philosophy to meddle with the foundations of the individual sciences; being the less successful discipline, its task is rather to seek guidance from the principles of rationality operative in the individual sciences.

Synthetic Aspects

Author: Philip Page
Publisher: Academic Press
ISBN: 9780080538198
Size: 10.54 MB
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Synthetic Aspects from the Author: Philip Page. During the last few years, the impact of organosulfur chemistry, especially in the areas of stereocontrolled processes, has led to an explosion of interest in the field. This book is intended to provide in-depth coverage of topics of interest throughout the whole range of organic sulfur chemistry, including bio-organic, physical organic, and synthetic aspects. This books covers such topics as: Synthetic transformations involving thiiranium ion intermediates Optically active (-ketosulfoxides and analogues in asymmetric synthesis Trends in the chemistry of 1,3-dithioacetals

Algal Biology And Biotechnology

Publisher: I. K. International Pvt Ltd
ISBN: 9380026196
Size: 44.84 MB
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Algal Biology And Biotechnology from the Author: . In the recent past, many advances have been made in the field of biology and biotechnology of algae, especially microalgae. This book includes chapters on taxonomy, diversity and physiology of blue-green algae as these organisms are most important from biotechnological point of view. Use of algae as biofertilizer, source of natural colours, bioactive compounds, phytochemicals with pharmaceutical and biotechnological applications, food and feed has been discussed. Environmental pollution is the major problem all over the world. The potential of algae in combating water pollution is also highlighted. Depleting fossil fuel is another concern and it is felt that there is a need for alternative renewable resources. Algae as a potential source of biofuel are also discussed in this book

Green Synthetic Approaches For Biologically Relevant Heterocycles

Author: Goutam Brahmachari
Publisher: Elsevier
ISBN: 0128005904
Size: 24.13 MB
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Green Synthetic Approaches For Biologically Relevant Heterocycles from the Author: Goutam Brahmachari. Green Synthetic Approaches for Biologically Relevant Heterocycles reviews this significant group of organic compounds within the context of sustainable methods and processes. Each clearly structured chapter features in-depth coverage of various green protocols for the synthesis of a wide variety of bioactive heterocycles classified on the basis of ring-size and/or presence of heteratoms(s). Techniques covered include microwave heating, ultrasound, ionic liquids, solid phase, solvent-free, heterogeneous catalysis, and aqueous media, along with multi-component reaction strategies. This book also integrates advances in green chemistry research into industrial applications and process developments. Green Synthetic Approaches for Biologically Relevant Heterocycles is an essential resource on green chemistry technologies for academic researchers, R&D professionals, and students working in medicinal, organic, natural product, and agricultural chemistry. Includes global coverage of a wide variety of green synthetic techniques Features cutting-edge research in the field of bioactive heterocyclic compounds Focuses extensively on applications, with numerous examples of biologically relevant heterocycles