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.

Solanapyrones e-g, antialgal metabolites produced by a marine fungus

Three new vinyl acetylenes from the marine red alga laurencia

Over the past decade, chemical investigations of benthic marine algae have illustrated that these organisms producea wide variety of structurally unique and biologically active secondary metabolites. Reviews of many aspects of these studies can be found in the various volumes of the treatise entitled ‘Marine Natural Products’ edited by Scheuer (1978–81). In general, it has been discovered that many of the red algae (Rhodophyta) produce halogenated terpenoids and acetogenins (compounds produced by acetate polymerization), and that the main halogen involved in this synthesis is bromine (Fenical 1975, 1982). Many of the halogenated metabolites have shown antimicrobial activities, cytotoxicities, and other pharmacological effects, and by virtue of their halogen substituents, these compounds have also been considered as leads for the development of new agrichemicals.

Antimicrobial and cytotoxic terpenoids from tropical green algae of the family Udoteaceae

Halogen chemistry of the red alga Bonnemaisonia

thus the discovery of a major new group of thesebacteria in marine sediments suggests that the ocean repre-sents an overlooked habitat from which to isolate theseimportant microorganisms. Given thatthe rate of discovery ofnew biologically active compounds from common soil actino-mycetes has been falling,

William Fenical

Papers

Solanapyrones e-g, antialgal metabolites produced by a marine fungus

Three new vinyl acetylenes from the marine red alga laurencia

Antimicrobial and cytotoxic terpenoids from tropical green algae of the family Udoteaceae

Halogen chemistry of the red alga Bonnemaisonia

Salinosporamide A: A Highly Cytotoxic Proteasome Inhibitor from a Novel Microbial Source, a Marine Bacterium of the New Genus Salinospora.