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A quantitative understanding of how sediment discharge from subglacial fluvial systems varies in response to glaciohydrological conditions is essential for understanding marine systems around Greenland and Antarctica and for interpreting sedimentary records of cryosphere evolution. Here we develop a graph-based approach, Graphical Subglacial Sediment Transport (GraphSSeT), to model subglacial fluvial sedimentary transport using subglacial hydrology model outputs as forcing. GraphSSeT includes glacial erosion of bedrock and a dynamic sediment model with exchange between the active transport system and a basal sediment layer. Sediment transport considers transport-limited and supply-limited regimes and includes stochastically evolving grain size, network-scale flow management, and tracking of detrital provenance. GraphSSeT satisfies volume balance and sediment velocity and transport capacity constraints on flow. GraphSSeT is demonstrated for synthetic scenarios that probe the impact of variations in hydrological, geological, and glaciological characteristics on sediment transport over multi-diurnal to seasonal time frames. For steady-state hydrology scenarios on seasonal timescales, we find a primary control from the scale and organisation of the channelised hydrological flow network. The development of grain-size-dependent selective transport is identified as the major secondary control. Non-steady-state hydrology is tested on multi-diurnal timescales for which sediment discharge scales with peak water input, leading to increased sediment discharge compared to the steady state. Subglacial hydrology models are being applied more broadly, and GraphSSeT extends this capacity to quantitatively define the volume, grain-size distribution, and detrital characteristics of sediment discharge that through comparison with the sediment record may enable improved knowledge of the glaciohydrological system and its impact on marine systems.

The title compound and its hydroxymethyl precursor have been fully characterised for the first time. The IR spectra, fully assigned 1H and 13C NMR spectra, and X-ray structures are presented for both compounds. Both compounds form hydrogen-bonded dimers in the crystal structures.

A series of fourteen O-ethyl-N-butylphenylphosphonamidates with benzyl ether substituents at the ortho position was prepared and fully characterised. Upon treatment with n-butyllithium in THF at RT, they underwent cyclisation in eight cases to give the novel 2,3-dihydrobenzo[d][1,3]oxaphospholes in moderate to low yield as a single diastereomer, for which the relative configuration was determined by X-ray diffraction in one case.

Application of the [1,2]-Wittig rearrangement and cyclisation approach to 3-arylphthalides has been evaluated for the synthesis of three bioactive natural products. While this is successful in the case of crycolide, providing the second synthesis of this compound, the more sterically demanding targets isopestacin and cryphonectric acid prove not to be amenable to this approach, with the 2,6-disubstituted aryl groups causing the failure of the rearrangement and alkylation steps, respectively. Direct oxidation of the substituted benzhydrols resulting from [1,2]-Wittig rearrangement using MnO2 provides a new route to 3-aryl-3-hydroxyisoindolinones, and this method has been used in the synthesis of two 3-aryl-3-benzyloxyisoindolinone anticancer agents.

A simplified synthesis of the title compound is reported and its 1H and 13C NMR data are fully assigned including determination of H–H and C–H coupling constants. Its X-ray structure has been determined for the first time. NMR data are also presented for the oxygen analogue.

Abstract Geothermal heat flow (GHF) is a key basal boundary condition for Antarctic ice‐sheet flow. Large‐scale variations are resolved by several recent models but knowledge of the smaller‐scale variations, crucial for ice sheet dynamics, is limited by unresolved variations in crustal radiogenic heat production. To define this at continent‐scale we use 3D gravity inversion constrained by seismic Moho estimates to identify variations in crustal composition and geometry beneath thick ice. Geochemically‐defined empirical relationships between density and heat production capture the global average trend and its variability, and allow to estimate from upper‐crust density spatial variations in radiogenic heat production. Significant variations are observed typically 1.2–1.6 μW/m3, and as high as 2 μW/m3 in West Antarctica. The contribution to GHF from these heat‐production variations is similarly variable, typically 16–24 mW/m2 and up to 60 mW/m2. The mapped variations are significant for correctly representing GHF in Antarctica.

The X-ray structure of the title compound, formed at low conversion in the reaction of thiosalicylic acid with thionyl chloride, has been determined. The acid chloride groups are oriented to permit an attractive non-bonding O…S interaction. Mechanisms are suggested for the formation of this unexpected product. 1H and 13C NMR data are also reported for the first time for the major reaction product, 2-mercaptobenzoyl chloride.

The X-ray structure of the title compound has been determined for the first time. This features ribbons formed by two parallel chains of molecules joined by C=O···H–N hydrogen bonding, which are then cross-linked by C=O···H–O hydrogen bonds. The structure is compared to those of closely related compounds.

The title dibromodisalicylaldehyde, obtained as a by-product in the m-chloroperoxybenzoic acid oxidation of 5-bromo-2-(methoxymethoxy)benzaldehyde, has been characterised by IR and NMR spectroscopy and X-ray diffraction. The structure features two independent molecules with a π–π stacking interaction between them.

A series of seven O-ethyl-N-butylphenylphosphonamidates with benzyl ether substituents at the para or meta position have been prepared and fully characterised. Upon treatment with n-butyllithium in THF at RT, these undergo Wittig rearrangement in six cases to give the novel phosphonamidate-substituted diarylmethanols in moderate to good yield.

The product formed by base-induced dimerisation of (2S,5S)-2-tert-butyl-5-methyl-1,3-dioxolan-4-one is shown by X-ray diffraction to be the title compound and not the isomeric fused-ring 1,3-dioxolane/1,3-dioxane-4-one structure proposed by previous researchers. The analogous compound derived from (2S,5S)-5-benzyl-2-tert-butyl-1,3-dioxolan-4-one has also been obtained and characterised.

While thiocarbonyl-stabilised phosphonium ylides generally react upon flash vacuum pyrolysis by the extrusion of Ph3PS to give alkynes in an analogous way to their carbonyl-stabilised analogues, two examples with a hydrogen atom on the ylidic carbon are found to undergo a quite different process. The net transfer of a phenyl group from P to S gives (Z)-configured 1-diphenylphosphino-2-(phenylsulfenyl)alkenes in a novel isomerisation process via intermediate λ5-1,2-thiaphosphetes. These prove to be versatile hemilabile ligands with a total of seven complexes prepared involving five different transition metals. Four of these are characterised by X-ray diffraction with two involving the bidentate ligand forming a five-membered ring metallacycle and two with the ligand coordinating to the metal only through phosphorus.

Abstract Background The seminal vesicles synthesise bioactive factors that support gamete function, modulate the female reproductive tract to promote implantation, and influence developmental programming of offspring phenotype. Despite the significance of the seminal vesicles in reproduction, their biology remains poorly defined. Here, to advance understanding of seminal vesicle biology, we analyse the mouse seminal vesicle transcriptome under normal physiological conditions and in response to acute exposure to the reproductive toxicant acrylamide. Mice were administered acrylamide (25 mg/kg bw/day) or vehicle control daily for five consecutive days prior to collecting seminal vesicle tissue 72 h following the final injection. Results A total of 15,304 genes were identified in the seminal vesicles with those encoding secreted proteins amongst the most abundant. In addition to reproductive hormone pathways, functional annotation of the seminal vesicle transcriptome identified cell proliferation, protein synthesis, and cellular death and survival pathways as prominent biological processes. Administration of acrylamide elicited 70 differentially regulated (fold-change ≥1.5 or ≤ 0.67) genes, several of which were orthogonally validated using quantitative PCR. Pathways that initiate gene and protein synthesis to promote cellular survival were prominent amongst the dysregulated pathways. Inflammation was also a key transcriptomic response to acrylamide, with the cytokine, Colony stimulating factor 2 (Csf2) identified as a top-ranked upstream driver and inflammatory mediator associated with recovery of homeostasis. Early growth response (Egr1), C-C motif chemokine ligand 8 (Ccl8), and Collagen, type V, alpha 1 (Col5a1) were also identified amongst the dysregulated genes. Additionally, acrylamide treatment led to subtle changes in the expression of genes that encode proteins secreted by the seminal vesicle, including the complement regulator, Complement factor b (Cfb). Conclusions These data add to emerging evidence demonstrating that the seminal vesicles, like other male reproductive tract tissues, are sensitive to environmental insults, and respond in a manner with potential to exert impact on fetal development and later offspring health.

The X-ray structure of the title compound was determined for the first time. There are four independent molecules that form a repeat unit packed in the crystal in alternating pairs with orthogonal orientation and further joined into infinite chains by hydrogen bonding.

The title compound, obtained by base-induced dimerization of 3-benzyloxazolidin-2-one, has been prepared and fully characterised. Its X-ray structure features hydrogen-bonded dimers involving the hydroxyl OH and amide carbonyl, forming a 14-membered ring.

The X-ray structures of three simple heterocyclic compounds have been obtained for the first time. Structures of both 3-acetyloxazolidin-2-one 1 and its unsaturated analogue 3-acetyloxazolin-2-one 3 show a planar imide nitrogen with the exocyclic C=O oriented anti to the ring N–C(=O) bond and negligible intermolecular interactions, a pattern consistent with previously reported analogues. In contrast the parent NH heterocycle, oxazolin-2(3H)-one 4, exists as hydrogen bonded dimers of two closely similar independent molecules but an unusual type of disorder involving exchange of the ring O and NH positions results in a very high R factor.

The X-ray structure of the title compound as the monohydrate has been determined and shows a complex structure with two independent molecules each of the compound and water and eleven distinct hydrogen bonding interactions. Its melting point has also been recorded for the first time.

Routine exposure to chemicals omnipresent in the environment, particularly the so-called endocrine-disrupting chemicals (EDCs), has been associated with decreased sperm quality and increased anomalies in testis. The decline in semen quality and testicular abnormalities have been attributed to the disruption of endocrine signaling as well as oxidative stress. The present study set out to examine the effect of short-term exposure of two common EDCs widely used in the plastic industry: Dibutyl Phthalate (DBP) and Bisphenol AF (BPAF). Our research objective was to focus on the post-testicular compartment of the epididymis, where spermatozoa acquire their functional capacity and are stored. The data obtained indicated no significant effect for either chemicals on sperm viability, motility or acrosome integrity. Neither of the EDCs had a noticeable effect on the structures of the testis and epididymis. However, substantial impact on the integrity of the sperm nucleus and DNA structure was evidenced by a significant increase in nuclear decondensation and DNA base oxidation. The damage observed was postulated to arise from the pro-oxidant properties of the EDCs generating excess of reactive oxygen species (ROS) and triggering a state of oxidative stress. This hypothesis was confirmed when the observed damage was largely blocked by co-administering EDCs with an evidenced-based antioxidant formulation.

(2S,5S)-5-Phenyl-2-t-butyl-1,3-dioxolan-4-one, readily derived from mandelic acid, undergoes the Michael addition to butenolide and 4-methoxy-β-nitrostyrene with the absolute configuration of the products confirmed by X-ray diffraction in each case. In the former case, thermal fragmentation gives the phenyl ketone, thus illustrating use of the dioxolanone as a chiral benzoyl anion equivalent. The Diels–Alder cycloaddition chemistry of (2S)-5-methylene-2-t-butyl-1,3-dioxolan-4-one, derived from lactic acid, has been further examined with the X-ray structures of four adducts determined. In one case, thermal fragmentation of the adduct gives a chiral epoxy ketone resulting from the dioxolanone acting as a chiral ketene equivalent, while in others the products give insight into the mechanism of the dioxolanone fragmentation process.

The title compound has been characterised for the first time by the full range of spectroscopic methods, and its X-ray structure shows hydrogen bonded stacks with iodine atoms aligned.

Lipids are dynamic biological molecules that play key roles in metabolism, inflammation, cell signalling and structure. They are biologically significant in the physiology of conception and reproduction. Many of the mechanisms surrounding equine conception and the early feto-maternal dialogue are yet to be understood at a biochemical level. Recently, lipidomic technologies have advanced considerably and analytical strategies have been enhanced and diversified. Consequently, in-depth lipidomic exploration now has the potential to reveal new lipid biomarkers and biochemical relationships that improve our understanding of the processes leading to efficient and successful reproduction. This review considers the role of lipids in conception and establishment of pregnancy, providing new insights into the enigmatic pathways governing early reproductive physiology of the mare.

The X-ray structure of the title compound, obtained as a byproduct in a natural product synthesis, has been determined and shows an unusual pattern featuring chains of molecules with both intra- and intermolecular hydrogen bonding of the OH groups.

The title epoxide was obtained by spontaneous epoxidation of the corresponding unsaturated imide in air or by peracid oxidation. Unambiguous assignment of the 1H- and 13C-NMR spectra is achieved by comparison between analogous compounds and its X-ray structure confirms the exo,exo-configuration.

Oxo-stabilised phosphonium ylides are found to form crystalline hydrogen-bonded adducts with aromatic carboxylic acids, as confirmed by X-ray diffraction. There is also strong hydrogen bonding in solution as indicated by 13C NMR spectroscopy and this confirmed adduct formation with acetic acid, benzamide, thiobenzamide, benzyl alcohol, benzenesulfinic acid and diphenylphosphinic acid. The X-ray structure of the benzamide adduct was also determined, showing a hydrogen-bonded dimeric structure. A bis(stabilised ylide) was also prepared and is found to form a complex hydrogen-bonded adduct with benzoic acid, ethanol and water.

Thirteen new crystal structures of cyclic NH carboximides have been determined and are compared with respect to the mode of intermolecular hydrogen bonding observed in the crystal. The structures include a new cyclobutane-fused succinimide, seven new simple bi- and tricyclic succinimides derived from Diels–Alder reactions of maleimide, three methylated glutarimides, a morpholinedione and adipimide, the first seven-membered ring NH carboximide to be structurally characterised. Overall, seven of the compounds adopt a ribbon structure, five show centrosymmetric dimers, and one has bonding between NH and a remote bridging ether oxygen. Halogen bonding was also detected in one case.

The unstable title compound has been characterized for the first time. Its melting point, UV, IR, 1H and 13C-NMR and high-resolution mass spectra are presented. The X-ray structure has also been determined and shows a rather long C–Br bond perpendicular to the otherwise planar molecule.

The X-ray structure of the title compound has been determined for the first time. Its molecular structure is in good agreement with those previously determined for similar benzyl halides and the angles between the ring–Cl bonds in adjacent molecules show values in good agreement with an early Zeeman quadrupole spectroscopy study.

The X-ray structure of the title compound has been determined for the first time. It shows the ring flip disorder common among thiophene-3-carbonyl derivatives and the occurrence of this phenomenon in the structures of such compounds is discussed.

Abstract Background The sperm protein IZUMO1 (Izumo sperm-egg fusion 1) and its recently identified binding partner on the oolemma, IZUMO1R, are among the first ligand-receptor pairs shown to be essential for gamete recognition and adhesion. However, the IZUMO1-IZUMO1R interaction does not appear to be directly responsible for promoting the fusion of the gamete membranes, suggesting that this critical phase of the fertilization cascade requires the concerted action of alternative fusogenic machinery. It has therefore been proposed that IZUMO1 may play a secondary role in the organization and/or stabilization of higher-order heteromeric complexes in spermatozoa that are required for membrane fusion. Results Here, we show that fertilization-competent (acrosome reacted) mouse spermatozoa harbor several high molecular weight protein complexes, a subset of which are readily able to adhere to solubilized oolemmal proteins. At least two of these complexes contain IZUMO1 in partnership with GLI pathogenesis-related 1 like 1 (GLIPR1L1). This interaction is associated with lipid rafts and is dynamically remodeled upon the induction of acrosomal exocytosis in preparation for sperm adhesion to the oolemma. Accordingly, the selective ablation of GLIPR1L1 leads to compromised sperm function characterized by a reduced ability to undergo the acrosome reaction and a failure of IZUMO1 redistribution. Conclusions Collectively, this study characterizes multimeric protein complexes on the sperm surface and identifies GLIPRL1L1 as a physiologically relevant regulator of IZUMO1 function and the fertilization process.

The X-ray structure of the title compound has been determined for the first time. Data on its 1H–13C-NMR coupling constants and 15N-NMR spectrum are also given.

The title compound was obtained in low yield in the condensation of ethyl pyruvate and lactic acid. Its structure is determined by NMR methods and x-ray diffraction and the mechanism for formation of this 1:2 adduct from the initial 1:1 adduct is considered.

The behaviour of 14 ortho-functionalised 2-aryloxazolines (11 of them prepared and characterised for the first time) with butyllithium has been examined. Significant limitations to the Wittig rearrangement of such systems are revealed. In terms of asymmetric Wittig rearrangement, good diastereoselectivity is obtained with a valine-derived 4-isopropyl oxazoline, but this is compromised by racemisation upon hydrolysis. More encouraging selectivity is achieved in the Wittig rearrangement of an acyclic phenylalanine-derived ortho-benzyloxy benzamide.

Abstract To discern temperature and compositional variations of the Australian upper mantle, we apply an integrative technique, which jointly interprets seismic tomography and gravity data. The final thermal model, obtained by changing the upper mantle composition according to the density variations, shows temperatures higher by 100–150°C in the Archean and Proterozoic upper mantle, with respect to the initial model based on a uniform “fertile” composition. In the North and West Australian cratons, the upper mantle is cold, with composition depleted in heavy constituents. This suggests the presence of an Archean lithosphere, which remained relatively undisturbed through the Proterozoic. Central Australia is predominantly characterized by a thick, low‐temperature lithosphere having a more fertile composition. Its shallow part is characterized by a thin layer of low‐velocity mantle, which is interpreted by our results as a thermal anomaly. However, this high‐temperature anomaly is hard to reconcile with the tectonic history of the region. A low‐density mineral phase, such as amphibole, may reduce the density relative to our assumed composition. Furthermore, we observe larger iron depletion in the Western Australian Craton than in the Proterozoic terranes. At the depths larger than 150 km, the depletion becomes negligible beneath the Proterozoic regions, while it also persists in the Western Australian Craton at the depths larger than 200 km.

The X-ray structure of the title compound has been determined and it is compared with those of other substituted benzyl chlorides reported previously. It has an atypically long CH2–Cl bond.

The title compound was obtained in low yield and spectroscopically characterised. Its X-ray structure was compared with the X-ray structures of other crystallographically-characterised 2-unsubstituted 1,3-dithiolanes.

The X-ray structure of the title compound has been determined and the structure shows an exo-configured planar dithiolanone ring. This is in contrast to the few previous dithiolanones to be characterised crystallographically, which are all twisted.

The title compound was obtained in moderate yield by a new and unexpected base-induced ring contraction from a 1,4-thiazine precursor. Its x-ray structure showing hydrogen bonded dimers was compared with those of other crystallographically characterised 2-acylpyrroles.

An early surviving copy of a periodic table of the elements wallchart is described and it is compared with other early versions of the periodic table. The status of chemistry teaching in St Andrews at the time and particularly the lectures of Professor Thomas Purdie are considered to show the context in which this periodic table would have been used and gain some appreciation of it pedagogical importance.

Three isomeric (benzyloxythienyl)oxazolines 9, 11 and 13 have been prepared and are found, upon treatment with a strong base, to undergo either Wittig rearrangement or intramolecular attack of the benzylic anion on the oxazoline function to give products derived from cleavage of the initially formed 3-aminothienofuran products. This pattern of reactivity is directly linked to the distance between the two reactive groups as determined by X-ray diffraction, with the greatest distance in 11 leading to exclusive Wittig rearrangement, the shortest distance in 13 giving exclusively cyclisation-derived products, and the intermediate distance in 9 leading to both processes being observed. The corresponding N-butyl amides were also obtained in two cases and one of these undergoes efficient Wittig rearrangement leading to a thieno[2,3-c]pyrrolone product.

Gas-phase reaction of 1,3-dithiolane-2-thione over molybdenum trioxide supported on pumice stone results in efficient conversion into 1,3-dithiolan-2-one. The solid reagent is regenerated on exposure to air and thus acts as a catalyst for the overall conversion of the thione and oxygen from the air into the ketone and sulfur dioxide. The process can be carried out under either dynamic vacuum or atmospheric pressure flow conditions and using a solid reagent prepared either by physical mixing of MoO3 with the support or by solution impregnation, with an isolated yield of up to 67% obtained.

The X-ray structure of the title compound contains eight molecules in the unit cell which form the basis of a herringbone arrangement of hydrogen bonded ribbons.

A prevalent cause of sperm dysfunction in male infertility patients is the overproduction of reactive oxygen species, an attendant increase in lipid peroxidation and the production of cytotoxic reactive carbonyl species such as 4-hydroxynonenal. Our previous studies have implicated arachidonate 15-lipoxygenase (ALOX15) in the production of 4-hydroxynonenal in developing germ cells. Here, we have aimed to develop a further mechanistic understanding of the lipoxygenase-lipid peroxidation pathway in human spermatozoa. Through pharmacological inhibition studies, we identified a protective role for phospholipase enzymes in the liberation of peroxidised polyunsaturated fatty acids from the human sperm membrane. Our results also revealed that arachidonic acid, linoleic acid and docosahexanoic acid are key polyunsaturated fatty acid substrates for ALOX15. Upon examination of ALOX15 in the spermatozoa of infertile patients compared to their normozoospermic counterparts, we observed significantly elevated levels of ALOX15 protein abundance in the infertile population and an increase in 4-hydroxynonenal adducts. Collectively, these data confirm the involvement of ALOX15 in the oxidative stress cascade of human spermatozoa and support the notion that increased ALOX15 abundance in sperm cells may accentuate membrane lipid peroxidation and cellular dysfunction, ultimately contributing to male infertility.

These data document the vitality of mature mouse oocytes (Metaphase II (MII)) and early stage embryos (zygotes) following exposure to the genotoxic chemotherapeutic agent, etoposide, in combination with PSC833, a selective inhibitor of permeability glycoprotein. They also illustrate the vitality of parthenogenetically activated and fertilized embryos following incubation with the calcium chelator BAPTA-AM (1,2-Bis(2-aminophenoxy)ethane- N,N,N′,N′-tetraacetic acid tetrakis (acetoxymethyl ester)), cycloheximide (an antibiotic that is capable of inhibiting protein synthesis), and hydrogen peroxide (a potent reactive oxygen species). Finally, they present evidence that permeability glycoprotein is not represented in the proteome of mouse spermatozoa. Our interpretation and discussion of these data feature in the article “Identification of a key role for permeability glycoprotein in enhancing the cellular defense mechanisms of fertilized oocytes” (Martin et al., in press) [1]. Keywords: Oocytes, Parthenote, Embryo, Vitality, Etoposide, PSC833, BAPTA-AM, Cyloheximide

The patterns adopted in the solid state structures of over 300 cyclic NH carboximides as determined by X-ray diffraction are reviewed. While the analysis shows that the majority of these fit into just a few common patterns, a significant number exhibit more complex and interesting patterns involving the other functional groups present in addition to the cyclic imide.