The results of a single-crystal structure determination when in CIF format can now be validated routinely by automatic procedures. In this way, many errors in published papers can be avoided. The validation software generates a set of ALERTS detailing issues to be addressed by the experimenter, author, referee and publication journal. Validation was pioneered by the IUCr journal Acta Crystallographica Section C and is currently standard procedure for structures submitted for publication in all IUCr journals. The implementation of validation procedures by other journals is in progress. This paper describes the concepts of validation and the classes of checks that are carried out by the program PLATON as part of the IUCr checkCIF facility. PLATON validation can be run at any stage of the structure refinement, independent of the structure determination package used, and is recommended for use as a routine tool during or at least at the completion of every structure determination. Two examples are discussed where proper validation procedures could have avoided the publication of incorrect structures that had serious consequences for the chemistry involved.

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Single-crystal structure validation with the program PLATON

Chemistry and biochemistry of 4-hydroxynonenal, malonaldehyde and related aldehydes.

https://pubs.rsc.org/en/content/articlepdf/2019/NP/C8NP00092A

Marine natural products.

Physiological and ecological constraints play key roles in the evolution of plant growth patterns, especially in relation to defenses against herbivores. Phenotypic and life history theories are unified within the growth-differentiation balance (GDB) framework, forming an integrated system of theories explaining and predicting patterns of plant defense and competitive interactions in ecological and evolutionary time. Plant activity at the cellular level can be classified as growth (cell division and enlargement) of differentiation (chemical and morphological changes leading to cell maturation and specialization). The GDB hypothesis of plant defense is premised upon a physiological trade-off between growth and differentiation processes. The trade-off between growth and defense exists because secondary metabolism and structural reinforcement are physiologically constrained in dividing and enlarging cells, and because they divert resources from the production of new leaf area. Hence the dilemma of plants: Th...

https://www.jstor.org/stable/pdfplus/2830650.pdf

The dilemma of plants: To grow or defend.

Advances in flavonoid research since 1992.

The development of new approaches for the treatment of cancer represents one of the greatest challenges of modern-day science. Beginning in the mid-1970s with the passage of the “National Cancer Act” and the establishment of the American National Institutes of Health’s National Cancer Institute (NCI), a worldwide effort was undertaken to discover and develop new treatments for this devastating disease. Not surprisingly, one of the most important approaches to this problem was the discovery of new anticancer drugs from natural sources. Programs were developed at NCI to access new plant species from common and remote environments throughout the world, resulting in the discovery of a significant number of lead molecules, such as taxol, that ultimately became part of a primary arsenal of drugs to treat this disease. Although the ocean is 70% of the Earth’s surface and 95% of its crust, this source was not examined until later. A major effort was undertaken by NCI to collect, extract, and assay a massive number of marine plants and animals. The results were impressive, and this achievement underscored the effort to pursue marine organisms. As of 2011, more than 20 marine-derived compounds are in clinical trials for various cancers, and two drugs Yondelis®(aka Trabectedin) and Havalen®(aka Eribulin Mesylate) are currently on the market for treatment of numerous cancer subtypes [1].

The Deep Oceans as a Source for New Treatments for Cancer

Two new cyclic hexadepsipeptides, exumolides A ( 1 ) and B ( 2 ) were produced by a marine fungus, identified as a Scytalidium sp., collected in the Bahamas. Two dimensional NMR methods, coupled with tandem mass spectrometry (MS-MS), were used to establish the structures of the new compounds. The exumolides exhibit antimicroalgal activity against the unicellular chlorophyte Dunaliella sp. at 20 μg ml −1 in liquid media cell growth assays.

Exumolides A and B: Antimicroalgal Cyclic Depsipeptides Produced by a Marine Fungus of the Genus Scytalidium.

Mechanismus der rk. von (1)delta(g)-angeregtem sauerstoff mit olefinen 2. mitt. ausschluss des konzertierten en-mechanismus als weg zur bldg. von allylhydroperoxiden

Aplasmomycin C: Structural Studies of a Marine Antibiotic.

The Pseudopterosins (I): A New Class of Antiinflammatory and Analgesic Diterpene Pentosides from the Marine Sea Whip Pseudopterogorgia elisabethae (Octocorallia).

William Fenical

Papers

The Deep Oceans as a Source for New Treatments for Cancer

Exumolides A and B: Antimicroalgal Cyclic Depsipeptides Produced by a Marine Fungus of the Genus Scytalidium.

Mechanismus der rk. von (1)delta(g)-angeregtem sauerstoff mit olefinen 2. mitt. ausschluss des konzertierten en-mechanismus als weg zur bldg. von allylhydroperoxiden

Aplasmomycin C: Structural Studies of a Marine Antibiotic.

The Pseudopterosins (I): A New Class of Antiinflammatory and Analgesic Diterpene Pentosides from the Marine Sea Whip Pseudopterogorgia elisabethae (Octocorallia).