Selection inventions

Selection patents in the chemical arts can take many forms. Selections may be made from a prior art broader range of compounds or compound uses (as in the current example) but are not so limited. For example, selection inventions might also be made from prior art chemical processes where, for example, a broad temperature range or reaction time is disclosed and a later, narrower embodiment is discovered that provides a patentably distinct process. Selection inventions are also sometimes referred to as improvement inventions because the later selection may provide some unexpected result or benefit that helps overcome challenges to patentability based on assertions of obviousness of the later discovery. Obviousness challenges and rebuttals to obviousness challenges are discussed in more detail in Chapter 8. 

Selection inventions are sometimes also referred to as improvement inventions. 

An unexpected effect in one species or subgenus selected from a known group and it is sufficient to render the species or subgenus patentable, because an inventive step can be acknowledged. Such inventions are called selection inventions. The principle of selection invention has been upheld by the EPO in many decisions. 

However, certain evidence might entitle your application to an allowable claim if it covers a salt with surprisingly and unexpectedly good activity. This evidence would support a so-called selection invention. Such an invention arises when a subclass of compounds chosen from a patented class possesses a demonstrable advantage. The advantage must be one that the other compounds lack. In this case, a claim to the subclass is allowable in a patent. 

Varying physical forms of neutral compounds may also be patentable and can create the basis for selection inventions. So, an amorphous solid may show better oral absorption and thereby higher blood levels than crystalline forms of the same drug. The amorphous substance would therefore offer a distinct therapeutic advantage. Similarly, a particular crystalline form can also bring such an advantage over other crystalline or amorphous states. 

Note that in the case of selection inventions claiming unexpected potency or selectivity, data to back that up may have been submitted to the patent examiner but never published in the application or patent so that no direct comparison can be made short of delving into the patent prosecution history to try and find it there. 

The field emission microscope (FEM), invented in 1936 by Muller [59, 60], has provided major advances in the structural study of surfaces. The subject is highly developed and has been reviewed by several groups [2, 61, 62], and only a selective, introductory presentation is given here. Some aspects related to chemisorption are discussed in Chapter XVII. 

Natural selection works through the complementary processes of mutation and genetic reassortment by recombination. The oligonucleotide-directed mutagenesis methods used in the foregoing examples do not allow for recombination instead, mutations are combined manually to optimize a protein sequence. Willem Stemmer at Maxygen invented a method of directed evolution that uses both mutation and recombination. This method, called... 

Throughout each chapter, clear structures, schemes, and figures accompany the text. Mechanism, reactivity, selectivity, and stereochemistry are especially addressed. Special emphasis is also placed on introducing both the logic of total synthesis and the rationale for the invention and use of important synthetic methods. In particular, we amplify the most important developments in asymmetric synthesis, catalysis, cyclization reactions, and organometallic chemistry. 

The homework assignments related to everyday life provided excellent students feedback. Despite not being foreseen in the LON teaching plan, due to great student interest, we prepared an exhibition of different home-made models for the coal-burning reaction. Most students were very inventive in the selection of materials for home made models to represent chemical reaction at the particle level. [Teacher from School N° 3, additional lesson after Section 2]... 

In a different context, a micropipette has been applied to monitor the current through a single-ion channel in a biological membrane. The patch-clamp technique invented by Sackmann and Neher [119] led to their Nobel Prize in medicine. The variations in channel current with voltage, concentration, type of ions, and type of channels have been explored. While the functions of specific channels, in particular their ionic selectivity, have been well known, only a handful of channels have the internal geometry and charge distribution determined. The development of a theory to interpret the mass of channel data and to predict channel action is still lacking. 

As 1,2,5-thiadiazole analogues, potent HlV-1 reverse transcriptase inhibitors, some simple 1,2,5-oxadiazoles, compounds 4-6 (Fig. 9), have been synthesized using the traditional Wieland procedure as key for the heterocycle formation [121]. Such as thiadiazole parent compounds, derivative with chlorine atoms on the phenyl ring, i.e., 5, showed the best anti-viral activity. Selectivity index (ratio of cytotoxic concentration to effective concentration) ranked in the order of 5 > 6 > 4. The activity of Fz derivative 6 proved the N-oxide lack of relevance in the studied bioactivity. These products have been claimed in an invention patent [122]. On the other hand, compound 7 (Fig. 9) was evaluated for its nitric oxide (NO)-releasing property (see below) as modulator of the catalytic activity of HlV-1 reverse transcriptase. It was found that NO inhibited dose-dependently the enzyme activity, which is hkely due to oxidation of Cys residues [123]. 

The most important example of this category is Raney nickel, which is extensively used in hydrogenation reactions in fine chemistry. The catalyst has been named after Murray Raney who invented this catalyst in 1924. It is prepared by the reaction of a powdered nickel-aluminium alloy with aqueous sodium hydroxide to selectively remove a large fraction of the aluminium component (.see Figure 3.12). The product consists of porous nickel with a high... 

Several studies have been reported on the application of conformational restraint to the 1,5-diaryl-pyrazole series in an attempt to provide compounds with modified properties. In one approach, a Sanofi-Synthelabo patent application claimed a series of conformationally restrained compounds, exemplified by compound (391). Compounds of the invention were stated to be CBi receptor antagonists with K[ values below 5 x 10 M and selectivity over CB2 receptors of at least 10-fold [274]. 

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