Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

Phd by thesis

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

Marine natural products.

A list of 1719 chemical compounds identified from headspace samples of floral scent is presented. The list has been compiled from some 270 published papers, including analyses of 991 species of flowering plants and a few gymnosperms, a sample including seed plants from 90 families and 38 orders. The compounds belong to seven major compound classes, of which the aliphatics, the benzenoids and phenylpropanoids, and, among the terpenes, the mono- and sesquiterpenes, occur in most orders of seeds plants. C5-branched compounds, irregular terpenes, nitrogen-containing compounds, and a class of miscellaneous cyclic compounds have been recorded in about two-thirds of the orders. Sulfur-containing compounds occur in a third of the orders, whereas diterpenes have been reported from three orders only. The most common single compounds in floral scent are the monoterpenes limonene, (E)-β-ocimene, myrcene, linalool, α- and β-pinene, and the benzenoids benzaldehyde, methyl 2-hydroxybenzoate (methyl salicylate), benzyl alcohol, and 2-phenyl ethanol, which occur in 54–71% of the families investigated so far. The sesquiterpene caryophyllene and the irregular terpene 6-methyl-5-hepten-2-one are also common and occur in more than 50% of the families. Orchidaceae are by far the best investigated family, followed by several families known to have many species with strongly scented flowers, such as Araceae, Arecaceae, Magnoliaceae, and Rosaceae. However, the majority of angiosperm families are still poorly investigated. Relationships between floral scent and pollination, chemistry, evolution, and phylogeny are briefly discussed. It is concluded that floral scent chemistry is of little use for phylogenetic estimates above the genus level, whereas the distribution and combinations of floral scent compounds at species and subspecific levels is a promising field of investigation for the understanding of adaptations and evolutionary processes in angiosperms.

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Diversity and Distribution of Floral Scent

The trans-influence: its measurement and significance

Recent developments in the synthesis and utilization of chiral sulfoxides.

Spiroacetals, cryptic ketodiols showing a hydroxyl group at both sides of a carbonyl whithin reachable distances are very widespread in nature. A group of 30 different structures, not including stereoisomers, represent volatile, less polar constituents of insect secretions. Five different systems were identified: 1,6-dioxaspirol[4.4]nonanes, 1,6-dioxaspiro[4.5]decanes, 1,6-dioxaspiro[4.6]undecanes, 1,7-dioxaspiro[5.5] undecanes, and 1,7-dioxaspiro[5.6]dodecanes. Some spiroacetals are insect pheromones: (2S,5R)-2-ethyl-1,6-dioxaspiro[4.4]nonane, chalcogran, 1, is a key component of the male produced aggregation pheromone of the spruce bark beetle, Pityogenes cha2cographus. In contrast, (5S,7S)-7-methyl-1,6-dioxaspiro[4.5]decane, 2, conophthorin, acts as a repellent or spacer in several bark beetles. Racemic 1,7-diosaspiro[5.5]undecane, olean, 5, is the female produced sex pheromone of the olive fly, Bactrocera (Dacus) oleae. The most widespread spiroacetal is 2,8-dimethyl-1,7-dioxaspiro[5.5]undecane, 8. Tt often forms a mixture of (E,E)- and (E,Z)-isomers, the (E,E)-isomer showing (2S,6R,8S)-configuration. In the solitary bee, Andrena wilkella, it serves as an aggregation pheromone. Present knowledge on structures and distribution of volatile spiroacetals is comprehensively compiled. Stereochemical aspects and mass spectrometric fragmentation patterns are discussed in detail to facilitate identifications of hitherto unknown compounds. Synthetic approaches to spiroacetals are classified and reviewed. Last but not least, facts and speculations on the biosynthesis of volatile spiroacetals are presented.

William Kitching

Papers

Spiroacetals in Insects

Chemistry of fruit flies

Organometallic Electrochemistry. I. Derivatives of Group IV-B Elements

Steroidal saponins from the roots of Asparagus racemosus

Organometallic Electrochemistry. II. Carbanion Stabilities