Derivatives scope

Das. B. C.. and E. Lederer Mass spectrometry of peptide derivatives Scope and Limitations. In Peptides 1971 (H. Nesvabda, Ed.), p. 253. Amsterdam North Holland Publishing Co. 1973. 

Hennis AD, PoUey ID, Long GS, Sen A et al. (2(X)1) Novel, efficient, palladium-based system for the polymerization of noibomene derivatives scope and mechanism. OiganometaUics 20 2802-2812... 

Other carbonyl compounds are within the scope of the reaction ketones give amides, and aldehydes yield nitriles and formyl derivatives of amines ... 

Special mention obviously must be given to sulfonamide derivatives of the thiazole ring. A complete coverage of the field is beyond the scope of this review however, some examples of their activity may be given here ... 

The scope of electrophilic aromatic substitution is quite large both the aromatic com pound and the electrophilic reagent are capable of wide variation Indeed it is this breadth of scope that makes electrophilic aromatic substitution so important Elec trophilic aromatic substitution is the method by which substituted derivatives of benzene are prepared We can gam a feeling for these reactions by examining a few typical exam pies m which benzene is the substrate These examples are listed m Table 12 1 and each will be discussed m more detail m Sections 12 3 through 12 7 First however let us look at the general mechanism of electrophilic aromatic substitution... 

The legally trained member of the interdisciplinary committee should provide insight as to the significance of the technological advance and as to whether any commercial product ultimately derived from the invention could be protected by an issued patent. Another important function of this person is to determine the scope of the invention based on preceding events, pubHcations, or activities which may have otherwise limited the breadth of the invention. To this end, U.S. law requires that an invention satisfy a number of prerequisites or requirements before issuing a patent novelty, nonobviousness, utiHty, and disclosure. 

Acylhydrazine derivatives of this general type provide one of the most convenient routes to a variety of 1,3,4-oxadiazoles, and the scope and limitations of this method are discussed in Chapter 4.23. 

Although there is very little scope for reactions of the above types with 1,2-benzisoxazole derivatives, the quaternary salts such as 2-methyl-3-phenyl-l,2-benzisoxazolium salt underwent base-catalyzed isomerization to the 1,3-benzoxazine shown in Scheme 83. This reaction is analogous to the formation of (202) above (67AHC(8)277). 

Subsequently, Beals and Brown expanded the scope of the earlier work from their laboratory to include the tetraoxaquaterene derived from furan and 3-pentanone. Using 3,3-difurylpentane and diethyl ketone in the presence of dry hydrogen chloride gas, the all-ethyl analog of 6 (mp 249°) was obtained in 20% yield. ... 

The halogenation-dehydrohalogenation of ketones and their derivatives is the most widely applied method for the preparation of unsaturated ketones, and the different combinations of alternatives which exist for both steps extend the scope of this approach. Consequently, this route will be discussed in considerable detail. 

Ehminations of HX to give double bonds offer considerable scope for selectivity and choice of reaction conditions. The dehydration of alcohols is the most common example of this class and may be achieved directly or through intermediate derivatives. In most cases, such derivatives are transient species formed in situ, but sometimes e.g. sulfonates, certain other esters and halides) they are isolated and characterized. Eliminations from jS-substituted ketones are very facile. The dehydration of jS-hydroxy ketones has been covered in section V. 

A later variation of the general method, which extends the scope to 20-ketones, involves reaction of the ketone with benzylamine to give the imine, followed by conversion to the A-acetyl derivative with acetic anhydride. Although the resulting compound also has a A -double bond, it does not react sufficiently fast with peracid, and a A -double bond can not be preserved. 

The NPRDS is an industry-wide system for monitoring the performance of selected systems and components at U.S. commercial nuclear power plants. Information in NPRDS is derived from a standardized format input report prepared by U.S. nuclear plant licensees. The plants are as)ced to submit failure reports on catastrophic events and degraded failures within the defined reportable scope reporting of incipient events is optional. Command faults are not reportable unless they malce an entire system unavailable. In addition, the plants are as)ced to file component engineering reports on all components within the selected systems and reportable scope. These reports contain detailed design data, operating characteristics, and performance data on the selected systems and components (over 3000 components, from approximately 30 systems, per unit). The selected systems are primarily safety systems. 

The procedure was largely ignored until the 1950s when interest in melanin-related substances and recognition of serotonin as a 5-hydroxy derivative stimulated exploration of the scope of the reaction. Nowadays, the Nenitzescu reaction is one of the most efficient processes for the preparation of 5-hydroxyindoles. 

While the majority of examples of the Fiesselmann reactions found in the literature involve thioglycolic acid or the corresponding thioglycolates, the scope of this reaction has been expanded to a variety of other a-mercaptocarbonyl derivatives. Some examples include a-mercapto aldehydes, ketones,and amides. Notably, when compound 33 is treated with 2-mercaptoacetamide, compound 34 was produced in 48% yield. ... 

In 1908, while working at University of Heidelberg, Auwers and Muller described the transformation of 4-methyl-2-cumaranone (3) to flavanol 6. Thus aldol condensation of 3 with benzaldehyde gave benzylidene derivative 4, which was brominated to give dibromide 5. Subsequent treatment of 5 with alcoholic KOH then furnished 2-methylflavonol 6. In the following years, Auwers published more extensively on the scope and limitations of this reaction. ... 

Hi) Dehydrogenation. j3-Carboline derivatives may be obtained from tetrahydro-)3-carbohnes by zinc dust distillation or high temperatmre dehydrogenation with selenium or palladium black. Many of the complex indole alkaloids may be degraded, with bond cleavage, to yield simple )3-carbolines under these conditions and this approach has become a standard method in structural elucidations. Examples are numerous but outside the scope of this review. 

In the previous review (91YGK205, 99H1157), we reported that l-hydroxy-4-nitroindole forms active ester derivatives by reaction with carboxylic acids, which can be applied to acylation of various nucleophiles. To expand the scope of the reaction and obtain novel fungicidal compounds, an attempt has been made to prepare derivatives of wasabi phytoalexin 109 (98P1959). 

The synthetic possibilities for isoxazoles and their hydrogenated derivatives by the formation of the 1—5 and 1—3 bonds are hardly exhausted it is to be expected that the scope of these interesting reactions will be considerably enlarged. 

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