Despite the large number of disparate approaches for the direct selective partial oxidation of methane, none of them has translated into an industrial process. The oxidation of methane to methanol is a difficult, but intriguing and rewarding, task as it has the potential to eliminate the prevalent natural gas flaring by providing novel routes to its valorization. This Review considers the synthesis of methanol and methanol derivatives from methane by homogeneous and heterogeneous pathways. By establishing the severe limitations related to the direct catalytic synthesis of methanol from methane, we highlight the vastly superior performance of systems which produce methanol derivatives or incorporate specific measures, such as the use of multicomponent catalysts to stabilize methanol. We thereby identify methanol protection as being indispensable for future research on homogeneous and heterogeneous catalysis.

The Direct Catalytic Oxidation of Methane to Methanol-A Critical Assessment.

Thioamides as useful synthons in the synthesis of heterocycles.

One of the remaining “grand challenges” in chemistry is the development of a next generation, less expensive, cleaner process that can allow the vast reserves of methane from natural gas to augment or replace oil as the source of fuels and chemicals. Homogeneous (gas/liquid) systems that convert methane to functionalized products with emphasis on reports after 1995 are reviewed. Gas/solid, bioinorganic, biological, and reaction systems that do not specifically involve methane functionalization are excluded. The various reports are grouped under the main element involved in the direct reactions with methane. Central to the review is classification of the various reports into 12 categories based on both practical considerations and the mechanisms of the elementary reactions with methane. Practical considerations are based on whether or not the system reported can directly or indirectly utilize O2 as the only net coreactant based only on thermodynamic potentials. Mechanistic classifications are based on whet...

Homogeneous Functionalization of Methane

Interpenetration in extended three-dimensional (3D) arrays has been investigated by a systematic analysis of the crystallographic structural databases, using an ad hoc version of the program package TOPOS. In this paper we describe the comprehensive results of our investigation of interpenetration in organic hydrogen-bonded 3D arrays from the Cambridge Structural Database. The great interest in the self-assembly of organic molecules into hydrogen-bonded supramolecular arrays has prompted us to investigate these systems at a rather unusual level; that is, beyond the formation of synthons, we have examined the topologies of the resulting networks and looked for their entanglements. Within 3D architectures we have extracted a complete list including 122 different motifs showing the phenomenon of interpenetration (76 unseen by the original authors). These organic networks include species assembled by a single or by different building blocks; they are discussed and classified according to the previously introd...

Interpenetrated Three-Dimensional Networks of Hydrogen-Bonded Organic Species: A Systematic Analysis of the Cambridge Structural Database

Although most antibiotics do not need metal ions for their biological activities, there are a number of antibiotics that require metal ions to function properly, such as bleomycin (BLM), streptonigrin (SN), and bacitracin. The coordinated metal ions in these antibiotics play an important role in maintaining proper structure and/or function of these antibiotics. Removal of the metal ions from these antibiotics can cause changes in structure and/or function of these antibiotics. Similar to the case of “metalloproteins,” these antibiotics are dubbed “metalloantibiotics” which are the title subjects of this review. Metalloantibiotics can interact with several different kinds of biomolecules, including DNA, RNA, proteins, receptors, and lipids, rendering their unique and specific bioactivities. In addition to the microbial-originated metalloantibiotics, many metalloantibiotic derivatives and metal complexes of synthetic ligands also show antibacterial, antiviral, and anti-neoplastic activities which are also briefly discussed to provide a broad sense of the term “metalloantibiotics.” © 2003 Wiley Periodicals, Inc. Med Res Rev, 23 No. 6, 697–762, 2003

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Structure and function of "metalloantibiotics".

Convenient approach to tetrahydro-quinolizin-4-ones by sequential addition of lithium allyldibutylmagnesate to N-allylpyridin-2-ones and ring-closing metathesis reactions

2-Pyridone is characterized by a very wide range of reactivity of a different nature, ranging from electrophilic aromatic substitution, CH–metal-mediated reactions, and NH/OH functionalization of both possible lactam/lactim tautomers, through cycloaddition, to nucleophilic addition and transformation of the tautomeric C=O/C–OH moiety. The high availability of 2-pyridones and the possibility of their far-reaching functionalization additionally increased their values. Therefore, they are very useful building blocks for the synthesis of structurally diverse piperidine and pyridine compounds, including naturally occurring 2-pyridones. This review reports on the use of simple 2-pyridones in the synthesis of alkaloids and alkaloids-inspired compounds based on the piperidine or pyridine framework. 1 	Introduction 2 	Structure, Availability, and Reactivity of 2-Pyridones 3 	Monocyclic Piperidine Alkaloids from 2-Pyridones 4 	Polycyclic Alkaloids, Their Derivatives, and Alkaloid-Inspired Compounds from 2-Pyridones 4.1 	New Ring Formation Involving C/N Atoms of the 2-Pyridone Ring 4.1.1 	Indolizine-Fused 2-Pyridones: Camptothecins and Related Compounds 4.1.2 	Other Indolizines from 2-Pyridones 4.1.3 	Compounds Bearing the Quinolizine Ring System 4.2 	New Ring Formation Involving C/C Atoms of the 2-Pyridone Ring 4.2.1 	C-2/C-3 Ring Fusion 4.2.2 	C-3/C-4 Ring Fusion 4.2.3 	C-4/C-5 Ring Fusion 4.2.4 	C-5/C-6 Ring Fusion 4.2.5 	C-2/C-4 Ring Bridge 4.2.6 	C-2/C-6 Ring Bridge 4.2.7 	C-3/C-5 Ring Bridge 4.2.8 	C-3/C-6 Ring Bridge 4.2.9 	C-4/C-6 Ring Bridge 5 	Conclusion

Pyridones – Powerful Precursors for the Synthesis of Alkaloids, Their Derivatives, and Alkaloid-Inspired Compounds

Reactions of β-keto thioamides with α,β-unsaturated aldehydes. Synthesis of 6-hydroxypiperidine-2-thiones and 6H-thiopyrans

Temperature coefficient of NH chemical shifts of thioamides and amides in relation to structure

An easy and novel approach to synthesize 4,5-diaryl functionalized 3,4-dihydropyrimidine-2(1H)-thiones via addition of aryllithiums to 5-aryl substituted pyrimidine-2(1H)-thiones, which could be regarded as a method complementary to the most widely used Biginelli-type synthesis, is described. In the reaction of aryllithiums with N–(Me)Bn substituted pyrimidine-2(1H)-thiones a high degree of regioselectivity of addition, leading to 4-aryl adducts, was achieved. Selected compounds tested for their in vitro anticancer activity against four human cancer cell lines showed the greatest activity against breast cancer (MCF7). 1-Benzyl-4-(3-hydroxyphenyl)-5-phenyl substituted 3,4-dihydropyrimidine-2(1H)-thione (10g) exhibiting 10-fold more potent activity than the best known monastrol (MON) stands as a promising candidate for further scaffold and asymmetric synthesis.

Regioselective synthesis of novel 4,5-diaryl functionalized 3,4-dihydropyrimidine-2(1H)-thiones via a non-Biginelli-type approach and evaluation of their in vitro anticancer activity

Jacek G. Sośnicki

Papers

Convenient approach to tetrahydro-quinolizin-4-ones by sequential addition of lithium allyldibutylmagnesate to N-allylpyridin-2-ones and ring-closing metathesis reactions

Pyridones – Powerful Precursors for the Synthesis of Alkaloids, Their Derivatives, and Alkaloid-Inspired Compounds

Reactions of β-keto thioamides with α,β-unsaturated aldehydes. Synthesis of 6-hydroxypiperidine-2-thiones and 6H-thiopyrans

Temperature coefficient of NH chemical shifts of thioamides and amides in relation to structure

Regioselective synthesis of novel 4,5-diaryl functionalized 3,4-dihydropyrimidine-2(1H)-thiones via a non-Biginelli-type approach and evaluation of their in vitro anticancer activity