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Oxidative stress generates a large amount of reactive oxygen species (ROS) and affects sperm quality via damaging sperm DNA and compromising the intracellular homeostasis in human spermatozoa. In assisted reproductive technology (ART), it is substantial to prevent spermatozoa from ROS attack. The pineal hormone melatonin has the natural antioxidant capacity and can scavenge ROS. To the best of our knowledge, however, there are presently no studies investigating if melatonin can protect human spermatozoa from heat-induced oxidative damage. Herein, we induced oxidative stress in human spermatozoa with heat treatment, and determined that melatonin could protect human spermatozoa from heat-induced oxidative stress. We first confirmed that heat stress-induced oxidative stress damaged human spermatozoa by decreasing sperm motility and viability. Furthermore, the pretreatment of human spermatozoa by melatonin was able to alleviate such damage by suppressing sperm mitochondrial ROS generation, increasing mitochondrial membrane potential, reducing the formation of the lipid peroxidation product, 4-HNE, and reducing sperm DNA damage and apoptosis. Collectively, these findings suggest that melatonin is useful as a potential treatment option for male infertility caused by heat-induced oxidative stress.

In an attempt to form 2-alkylidene-1,3-oxazolidines, chiral 2-oxazolines have been N-alkylated and N-acylated. Two new N-methyloxazolinium salts have been prepared and characterised but base treatment resulted in their decomposition. In contrast, attempts to isolate three N-benzoyloxazolinium salts gave the products of their ring hydrolysis: unsymmetrically diacylated amino alcohols whose structure was confirmed by x-ray diffraction in one case. Overall the method allows stepwise regiospecific N,O-diacylation of 1,2-amino alcohols. Postprint

Male and female germ lines are vulnerable to oxidative stress. In spermatozoa, such stress triggers a lipid peroxidation cascade that culminates in the generation of electrophilic lipid aldehydes that bind to DNA and a raft of proteins involved in the delivery of functionally competent cells. One set of targets for these aldehydes are the proteins of the mitochondrial electron transport chain. When this interaction occurs, mitochondrial ROS generation is enhanced leading to the sustained generation of oxidative damage in a self-perpetuating cycle. Such damage affects all aspects of sperm function including motility, sperm-egg recognition, acrosomal exocytosis and sperm-oocyte fusion. Oxidative stress in the male germ line also attacks the integrity of sperm DNA with potential impacts on the developmental capacity of embryos and the health and wellbeing of the offspring. Potential pathways of reactive oxygen species (ROS) generation in male germ cells could involve enhanced lipoxygenase activity, activation of NADPH oxidase and/or electron leakage from mitochondria. Similarly, in the female germ line, both the induction of oocyte senescence following ovulation and the deterioration of oocyte quality with maternal age appear to involve the generation of oxidative damage. In this case, the mitochondria appear to be a particularly important source of ROS compromising the viability and fertilizability of the oocyte and interfering with the normal segregation of chromosomes during meiosis. In light of these considerations, antioxidants should have some role to play in the preservation of reproductive function in both men and women; however, we still await appropriate trials to test this hypothesis.

Asymmetric access to α-hydroxy-1,4-diketones has been achieved by direct ene coupling of silyl enol ethers with glyoxal electrophiles, mediated by a chiral N,N′-dioxide–nickel(II) complex catalyst. Successful union of a polyketide silyl enol ether with an α-quaternary glyoxal, generated by dioxirane oxidation of an α-diazo ketone, models a proposed C5–C6 disconnection of the polyketide and spirocyclic imine domains of the marine natural product, portimine.

2-Bromo-1,3-butadienes are demonstrated to be effective substrates for tandem Diels-Alder/transition metal cross-coupling reaction sequences. Intermolecular cycloaddition of a 2-bromo-1,3-diene with activated dienophiles proceeded under Lewis acid catalysis in generally high yields with good to excellent endo diastereoselectivity. The resulting vinyl bromide cycloadducts underwent subsequent Stille and Suzuki cross-couplings under standard conditions in good yields. Both the Diels-Alder and cross-coupling steps were highly tolerant of a range of functionalities and protecting groups. The use of the bromine substituent as both a cycloaddition directing group and cross-coupling nucleofuge avoids extra steps required to install and remove the more commonly used silyl enol ethers and enol sulfonates for each transformation and gives full control of the alkene regiochemistry throughout the reaction sequence. The 2-bromo-1,3-dienes were conveniently prepared in three steps from readily available aldehydes and established as hydrolytically stable and practical synthetic intermediates.

Two of the three published sets of 1H and 13C NMR data for bicyclo[2.2.1]hepta-2,5-diene-2,3-dicarboxylic anhydride have been found to actually be those of the corresponding diacid. The NMR spectroscopic distinction between these two compounds is clarified and 1JC–H values are reported for the anhydride, the diacid and a related diester. The X-ray structure of the diacid has been determined and features chains of molecules involving both intra- and inter-molecular hydrogen bonding. Postprint

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.

We would like to thank the Engineering and Physical Sciences Research Council and CRITICAT Centre for Doctoral Training for financial support [Grant Code: EP/L016419/1]. Molecular structures of (R)-2,2'-dimethyl-1,1'-binaphthyl [monoclinic, a = 11.24420 (11), b = 10.56190 (9), c = 13.27180 (13) Å, β = 90.7041 (9)º, space group P21] and (±)-2-bromomethyl-2'-dibromomethyl-1,1'-binaphthyl [triclinic, a = 9.4637 (14), b = 9.9721 (18), c = 9.9922 (19) Å, α = 100.093 (5), β = 97.141 (5), γ = 92.585 (4)º, space group P-1] are reported and compared with those of other simple 2,2'-disubstituted-1,1'-binaphthyls. Postprint

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.

Stereoselective synthesis of the C4-C16 polyketide fragment of portimines A and B is reported, enabled by our previously established method for the stereoselective synthesis of syn-α,α'-dihydroxyketones. The preparation of this advanced fragment provides insights useful for the total synthesis of portimines A and B. An asymmetric Evans aldol reaction was used to install the C10-C11 adjacent stereogenic centers before incorporation of indantrione, followed by epoxidation and epoxide opening to forge the challenging syn-α,α'-dihydroxyketone functionality.

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. Publisher PDF

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. Publisher PDF

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. Publisher PDF

The close similarity in patterns of bands in the microwave spectra of the isomeric 1,2,3- and 1,2,4-triazines has enabled assignment for the 1,2,3-isomer. Pure rotational transitions with J up to 65 were identified and fitted to a Watson-type Hamiltonian: A = 6334.157(14)., B = 6271.289(14), C = 3151.230(14). A and B thus show near degeneracy. Coupled cluster calculations which include both singles, doubles and selected triple excitations (CCSD(T)), give very close agreement with the spectral data. The theoretical structure which includes estimates of the 14N quadrupole coupling, not determined in the spectrum, is described. Postprint

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. Publisher PDF

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. Publisher PDF

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.

Synchrotron-based photoelectron spectra (PES) of norbornadiene (NBD) and quadricyclane (QC) differ significantly from those in previous studies. The adiabatic ionization energy (AIE1) for NBD, assigned to the 2B1 state at 8.279 eV, shows a progression of 18 members with decreasing vibration frequency from 390 cm−1 to 340 cm−1; our calculated frequency is 381 cm−1. Similarly, the AIE1 for QC at 7.671 eV, assigned to the 2B2 state, discloses a vibrational progression of nine or more members with vibration frequency decreasing from 703 cm−1 to 660 cm−1; our calculated vibration frequency is 663 cm−1. These AIEs, determined by coupled cluster and fourth order Møller–Plesset perturbation theory, were very similar to the corresponding second order perturbation theory results. The calculated AIE symmetry sequences are 2B1 < 2A1 < 2A2 < 2B2 for NBD and 2B2 < 2A2 < 2B1 < 2A1 for QC. The overall PES vertical ionization energy profiles for both compounds were closely reproduced by Tamm–Dancoff approximation energies and intensities. The vibrational structure of the ionic states, determined using Franck–Condon methods, gave a good account of the observed spectra, but the observed envelopes for both IE1 are complex sets of vibrations, rather than single progressions. The NMR spectra for QC showed residual second order properties at 300 MHz; both QC and NBD have been theoretically analyzed in greater detail using AA/BB/CC/XX/ spectra, where all H are coupled; the magnetic shielding and spin–spin coupling constants obtained are similar to experimental values. Postprint Postprint

A series of amino acid-derived chiral benzylthio alcohols have been prepared and characterized. A chiral mercapto alcohol derived from S-leucine has been used to form three chiral 2,4-disubstituted 1,3-oxathiolanes. One of these has been oxidized to the S-oxide and another to the S,S-dioxide. The cis and trans isomers have been characterized by 1H NMR in each case and it appears that thermal epimerisation at C-2 is possible at the sulfoxide oxidation state. The X-ray structure of major trans diastereomer of 2-phenyl-4-isobutyl-1,3-oxathiolane S,S-dioxide shows an envelope conformation with oxygen at the flap and an internal angle at sulfur of just 93.8°. This compound fragments upon flash vacuum pyrolysis at 700°C to give SO2, benzaldehyde and 4-methylpent-1-ene.

A second polymorph of 4-aminobenzyl alcohol [orthorhombic, a = 8.95051(15), b = 5.8248(1), c = 12.1645(2) Å, space group Pna21] shows a "herringbone" structure with stacks of hydrogen-bonded molecules when viewed down the b-axis. Publisher PDF

We thank EPSRC (UK) for a studentship to ANG. Ten new oxo-stabilised phosphonium ylides containing substituted thiophene groups, as well as two deuterium-labelled analogues, are prepared and fully characterised. Upon flash vacuum pyrolysis at 800 °C, the simpler examples undergo extrusion of Ph3PO coupled with domino cyclisation to give thieno[3,2-b]furan and thieno[3,4-b]furan products but the corresponding approach to a thieno[2,3-b]furan fails. One ylide designed to give a thieno[3,4-b]furan instead gives phenylbutadiyne and 2-phenyl-3-vinylthiophene at 725 °C and the mechanism of this unusual process is elucidated by deuterium labelling. Attempts to access more complex heterocyclic products from extended methoxythienyl ylides failed. Two ylides bearing a 3-methyl-2-thienylacryloyl group gave 5-benzylbenzothiophene, 5-(α-methylbenzyl)benzothiophene and fluoreno[3,4-b]thiophene upon FVP at 800 °C and the mechanism was again elucidated by deuterium labelling. Postprint

A synchrotron-based vacuum ultraviolet (VUV) absorption spectrum of norbornadiene (NBD) is reported, and the extensive vibrational structure obtained has been analyzed. The previously known 5b 13s-Rydberg state has been reinterpreted by comparison with our recent high-resolution photoelectron spectral analysis of the X 2B 1 ionic state. Additional vibrational details in the region of this Rydberg state are observed in its VUV spectrum when compared with the photoelectron 2B 1 ionic state; this is attributed to the underlying valence state structure in the VUV. Valence and Rydberg state energies have been obtained by configuration interaction and time-dependent density functional theoretical methods. Several low-lying singlet valence states, especially those that arise from ππ* excitations, conventionally termed NV 1 to NV 4, have been examined in detail. Their Franck-Condon (FC) and Herzberg-Teller (HT) profiles have been investigated and fitted to the VUV spectrum. Estimates of the experimental 0 0 band positions have been made from these fits. The anomaly of the observed UV absorption by the 1A 2 state of NBD is attributed to HT effects. Generally, the HT components are less than 10% of the FC terms. The calculated 5b 13s lowest Rydberg state also shows a low level of HT components. The observed electron impact spectra of NBD have been analyzed in detail in terms of triplet states.

The authors thank EPSRC (UK) for a DTA studentship (Grant No. EP/P501768/1). Six stabilised phosphonium ylides bearing ortho-benzylaminophenyl and cinnamoyl (or a heterocyclic analogue) groups have been prepared and upon flash vacuum pyrolysis at 800 °C were found to undergo cascade cyclization processes to give mainly 3-styrylquinolines but also in some cases ring-fused carbazoles and other fused-ring heterocyclic products. By starting with an appropriate ring-methylated precursor the natural product Eustifoline D was obtained in 19% yield in the pyrolysis in addition to the 3-(2-furylethenyl)quinoline (46%). Postprint

The authors thank EPSRC (UK) for a studentship to ANG. Thirty-six new stabilised phosphonium ylides designed to undergo thermal loss of Ph3PO and radical domino cyclisation have been prepared and are generally found to undergo the desired reaction under flash vacuum pyrolysis conditions at 850 °C. A wide range of tetra- and penta-cyclic fused ring heterocycles, many previously unknown, are thus formed in moderate to high yield in a single step. By using suitably substituted starting materials, substituents such as CH3 and Cl can be installed at various positions in the products. The method has also been demonstrated in a combinatorial mode to generate a small library of twelve fused ring heterocycles in a single pyrolysis. Postprint

The authors are grateful to EPSRC and Glaxo-Wellcome (now GSK) for their support of this work through a CASE Studentship to TM. Pyrolysis, either neat or in diphenyl ether solution, results in the conversion of both 4-triphenylphosphoranylidenetetrahydrofuran-2,3,5-trione and 4-triphenylphosphoranylidenetetrahydrothio-phene-2,3,5-trione into 3,5-bis(triphenylphosphoranylidene)cyclopentane-1,2,4-trione. These reactions involve extrusion of CO2 or COS to give 3-triphenylphosphoranylidenecyclopropane-1,2-dione which further loses CO to give triphenylphosphoranylideneketene. The precise way in which these two reactive phosphorus compounds combine to give the observed product has been examined by chemical and isotopic labelling studies. Cyclotrimerization of triphenylphosphoranylideneketene upon thermolysis in diphenyl ether has also been observed for the first time. The erroneous literature interpretation of the 13C NMR spectrum for triphenylphosphoranylideneketene is corrected. Publisher PDF

This work was supported by B.P. Flash vacuum pyrolysis at 600 °C through glass wool coated with freshly sublimed magnesium is examined as a preparative method for dehalogenative coupling in organic synthesis. Substituted benzylidene chlorides give predominantly the corresponding stilbenes and in some cases these are readily isolated in pure form. With an ortho-halogen substituent, additional cyclisation gives phenanthrenes but the method is not compatible with the presence of several reactive groups. An ortho-methoxy substituent leads to unexpected formation of mono- and dimethyl products. With 1,4-bis(dihalomethyl)benzenes, halogenated polymers are deposited directly from the gas phase via generation of halogenated p-xylylenes. The 1,2- and 1,3-isomers lead respectively to benzocyclobutadiene, isolated as a dimer, and to pyrene. The 1,4-bis(trihalomethyl)benzenes give more highly halogenated polymers directly from the gas phase via halogenated p-xylylenes. While halobenzenes generally give the corresponding benzenes and biphenyls, 1,2-dihalobenzenes additionally produce triphenylene in preparatively useful yield by a process not involving intermediacy of free benzyne. Postprint

Lipid peroxidation products, such as 4-hydroxynonenal (4HNE), are causative agents responsible for extensive protein damage within the male and female germlines. Recently, we have demonstrated that 4HNE production can initiate the proteolytic degradation of the molecular chaperone Heat Shock Protein A2 (HSPA2) in male germ cells. These events may be partially responsible for HSPA2 deficiency in the spermatozoa of patients that repeatedly fail in vitro fertilization. Given this, mechanisms that limit the production of 4HNE will be highly advantageous for the preservation of male fertility. The propagation of 4HNE in somatic cells has been linked to the enzymatic actions of arachidonate 15-lipoxygenase (ALOX15), a member of the lipoxygenase family of proteins. In view of this association, this study sought to explore ALOX15 as a physiological target to manipulate the levels of 4HNE produced in the male germline. Herein, we have demonstrated that ALOX15 is markedly upregulated in response to oxidative stress in round spermatids and the GC-2 cell line. Pharmacological inhibition of ALOX15 in GC-2 cells resulted in a significant reduction in both mitochondrial and cytoplasmic reactive oxygen species, as well as a dramatic reduction in 4HNE. Importantly, the reduced bioavailability of this aldehyde appears to confer positive downstream effects to its target proteins such that HSPA2 could be protected from damage by 4HNE. Taken together, these results suggest that the actions of ALOX15 are intimately tied to the production of 4HNE. Thus, the ALOX15 protein may be a promising new target for the mitigation of germline oxidative stress.

Artificially generated radiofrequency-electromagnetic energy (RF-EME) is now ubiquitous in our environment owing to the utilization of mobile phone and Wi-Fi based communication devices. While several studies have revealed that RF-EME is capable of eliciting biological stress, particularly in the context of the male reproductive system, the mechanistic basis of this biophysical interaction remains largely unresolved. To extend these studies, here we exposed unrestrained male mice to RF-EME generated via a dedicated waveguide (905 MHz, 2.2 W/kg) for 12 h per day for a period of 1, 3 or 5 weeks. The testes of exposed mice exhibited no evidence of gross histological change or elevated stress, irrespective of the RF-EME exposure regimen. By contrast, 5 weeks of RF-EME exposure adversely impacted the vitality and motility profiles of mature epididymal spermatozoa. These spermatozoa also experienced increased mitochondrial generation of reactive oxygen species after 1 week of exposure, with elevated DNA oxidation and fragmentation across all exposure periods. Notwithstanding these lesions, RF-EME exposure did not impair the fertilization competence of spermatozoa nor their ability to support early embryonic development. This study supports the utility of male germ cells as sensitive tools with which to assess the biological impacts of whole-body RF-EME exposure.

Authors thank the Engineering and Physical Sciences Research Council and CRITICAT Centre for Doctoral Training for financial support [Grant code: EP/L016419/1]. 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. Publisher PDF

The chemistry of the known thieno[b]pyrrolones and dihydrothieno[b]pyrrolones, as well as ring-fused analogs, is reviewed up to the end of 2018 with 200 literature references. For each system, the properties, reactivity, synthesis, and applications are systematically covered.

In this chapter we outline the history of reactive oxygen species (ROS) and spermatozoa, starting with some of the foundation experiments conducted by John MacLeod in 1943. Historically, we have seen that if ROS come into contact with spermatozoa in high enough concentrations, they trigger peroxidative damage that culminates in aldehyde by-products that are detrimental to cell function. This can be demonstrated in a number of ways, but for the most part, this has been achieved by external addition of ROS or exposure to ROS-generating in vitro systems. We also discuss the many challenges that await this field, including the various pitfalls associated with measuring ROS that make it difficult to ascertain if these metabolites are causally involved in the etiology of male-factor infertility or whether they are just playing a passive role. Today, with improved methods of measuring ROS, together with a better knowledge of the pathways associated with peroxidative damage, the involvement of oxidative stress on sperm function should become clearer.

This material is based upon work supported by the National Science Foundation under Grant Nos. CHE-1057796 and CHE-1952289 at the University of Arizona. A sample of doubly-substituted 15N formamidinium formate was synthesized and the microwave spectrum was measured in the 5.6-14.2GHz frequency range using a Flygare-Balle type pulsed beam Fourier transform microwave (MW) spectrometer. A total of 13 a-type rotational transitions were measured and fitted to obtain the rotational constants and centrifugal distortion constants for the 15N substituted isotopologue. The rotational constants and centrifugal distortion constants determined have the following values: A=5808.02(18)MHz, B=2127.008(2)MHz, C=1557.615(2)MHz, DJ=0.60(11)kHz, DJK=4.95(71)kHz and δJ = -0.138(24)kHz. Tunneling splittings were searched for, but not observed. NMR spectra for this compound are reported including values of δC, δN, 1JCH, 1JCN and 2JNH in CD3SOCD3, CD3OD and D2O. The occurrence of NH to ND exchange in D2O allowed the fortuitous measurement of 1JND. Postprint

Evidence is presented for expression of the insulin receptor on the surface of mammalian spermatozoa as well as transcripts for the receptor substrate adaptor proteins (IRS1-4) needed to mediate insulin action. Exposure to this hormone resulted in insulin receptor phosphorylation (pTyr972), activation of AKT (pSer473) and the stimulation of sperm motility. Intriguingly, the male germ line is also shown to be capable of generating insulin, possessing the relevant mRNA transcript and expressing strong immunocytochemical signals for both insulin and C-peptide. Insulin could be released from the spermatozoa by sonication in a concentration-dependent manner but was not secreted in response to glucose, fructose or stimulation with progesterone. However, insulin release could be induced by factors present in human uterine lavages. Furthermore, the endometrium was also shown to possess the machinery for insulin production and action (mRNA, insulin, C-peptide, proprotein convertase and insulin receptor), releasing insulin into the uterine lumen prior to ovulation. These studies emphasize the fundamental importance of extra-pancreatic insulin in regulating the reproductive process, particularly in the support of spermatozoa on their perilous voyage to the site of fertilization.

Seminal vesicles are an integral part of the male reproductive accessory gland system. They produce a complex array of secretions containing bioactive constituents that support gamete function and promote reproductive success, with emerging evidence suggesting these secretions are influenced by our environment. Despite their significance, the biology of seminal vesicles remains poorly defined. Here, we complete the first proteomic assessment of mouse seminal vesicles and assess the impact of the reproductive toxicant acrylamide. Mice were administered acrylamide (25 mg/kg bw/day) or control daily for five consecutive days prior to collecting seminal vesicle tissue. A total of 5013 proteins were identified in the seminal vesicle proteome with bioinformatic analyses identifying cell proliferation, protein synthesis, cellular death, and survival pathways as prominent biological processes. Secreted proteins were among the most abundant, and several proteins are linked with seminal vesicle phenotypes. Analysis of the effect of acrylamide on the seminal vesicle proteome revealed 311 differentially regulated (FC ± 1.5, p ≤ 0.05, 205 up-regulated, 106 downregulated) proteins, orthogonally validated via immunoblotting and immunohistochemistry. Pathways that initiate protein synthesis to promote cellular survival were prominent among the dysregulated pathways, and rapamycin-insensitive companion of mTOR (RICTOR, p = 6.69E-07) was a top-ranked upstream driver. Oxidative stress was implicated as contributing to protein changes, with acrylamide causing an increase in 8-OHdG in seminal vesicle epithelial cells (fivefold increase, p = 0.016) and the surrounding smooth muscle layer (twofold increase, p = 0.043). Additionally, acrylamide treatment caused a reduction in seminal vesicle secretion weight (36% reduction, p = 0.009) and total protein content (25% reduction, p = 0.017). Together these findings support the interpretation that toxicant exposure influences male accessory gland physiology and highlights the need to consider the response of all male reproductive tract tissues when interpreting the impact of environmental stressors on male reproductive function., Graphical abstract, Highlights • First proteomic characterization of the mouse seminal vesicle tissue. • Secreted proteins are among the most abundant proteins in the seminal vesicle tissue. • Paternal exposure to reproductive toxicant acrylamide alters seminal vesicle proteome. • Acrylamide treatment results in reduced seminal vesicle secretory capacity., In Brief Seminal vesicles produce bioactive constituents that support gamete function and promote reproductive success. Despite their significance, seminal vesicle biology remains poorly defined. Here, we have exploited proteomics to generate the first mechanistic insights into mouse seminal vesicles in normal physiology and pathology. Our collective data affirm the hypothesis that seminal vesicles are sensitive to environmental factors and exposures in a manner that may have consequences for fetal development and later offspring health.

The NBS bromination of 1,4-dimethoxy-2,3-dimethylbenzene has been examined under a variety of conditions in both 1,1,1-trichloroethane and benzotrifluoride. Four different bromination products have been isolated including the previously unknown 1-bromo-4-bromomethyl-2,5-dimethoxy-3-methylbenzene whose single crystal X-ray structure is presented. The synthetically useful 2,3-bis(bromomethyl)-1,4-dimethoxybenzene is readily prepared using either solvent and it has been converted into new sulfur-containing quinone derivatives Postprint

Cycloaddition of 3,4-dibromofuran with azo diesters proceeds by a Diels–Alder reaction followed by a novel rearrangement to give 3,5-dibromotetrahydropyridazin-4-ones. Variable-temperature NMR spectroscopy shows four separate conformations at low temperature attributed to restricted rotation about the carbamate functions. The ethyl compound decomposes upon storage with loss of the carbamate groups and aromatisation to give a simple bromohydroxypyridazinium salt. Publisher PDF

A range of twelve stabilised phosphonium ylides containing tetrahydrofuran, tetrahydropyran or 2,2-dimethyl-1,3-dioxolane rings have been prepared and fully characterised, including one X-ray structure determination of each type. The X-ray structures confirm the P=C and C=O functions to be syn and all the compounds undergo thermal extrusion of Ph3PO to give the corresponding alkynes. In some cases there is also competing loss of Ph3P to give different carbene-derived products and evidence has been obtained for the generation of 2-phenyloxete in this way. Raising the pyrolysis temperature leads in several cases to new secondary reactions of the alkyne products involving a sequence of alkyne to vinylidene isomerisation, intramolecular CH insertion, and retro Diels Alder reaction. Publisher PDF

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 title compound has been 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 is compared with those of other crystallographically characterized 2-acylpyrroles. Publisher PDF