Synthesis, conformational stability and molecular structure of 4-aryl- and 4,5-diaryl-1,8-bis(dimethylamino)naphthalenes.

4-Bromo- and 4,5-dibromo-1,8-bis(dimethylamino)naphthalenes were arylated with arylboronic acids under Suzuki reaction conditions to provide 4-aryl- and 4,5-diaryl-1,8-bis(dimethylamino)naphthalenes, respectively. The interaction of 4,5-dibromo-1,8-bis(dimethylamino)naphthalene with pyridin-3-ylboronic acid was accompanied by heterocyclization leading unexpectedly to the formation of N3,N3,N4,N4-tetramethylacenaphtho[1,2-b]pyridine-3,4-diamine. Dynamic 1H NMR experiments showed fast interconversion between syn and anti conformers of 4,5-diaryl-1,8-bis(dimethylamino)naphthalenes in CDCl3 solution at room temperature. The free energy of the rotational isomerization was determined to be ∼14.0 kcal mol-1 for 4,5-di(m-tolyl) and 4,5-di(naphthalen-2-yl) derivatives. X-ray analysis of 4,5-diaryl-1,8-bis(dimethylamino)naphthalenes revealed a high degree of structural deformation due to internal steric repulsions between both peri-dimethylamino and peri-aryl groups. In crystals, 4,5-di(naphthalen-1-yl)-1,8-bis(dimethylamino)naphthalene molecules exist exclusively in the most stable anti-out form, while for 4,5-di(naphthalen-2-yl) and 4,5-di(m-tolyl) counterparts, only the syn-form is realized. The introduction of two peri-aryl substituents in the 1,8-bis(dimethylamino)naphthalene scaffold affected the basic properties, making the 4,5-diphenyl derivative 0.7 pKa units less basic. The protonation of 4,5-diaryl-1,8-bis(dimethylamino)naphthalenes leads to dramatic changes in their structures. Compared to the corresponding bases, the inter-nitrogen distance in these salts noticeably decreases whereas peri-aromatic rings move away from each other demonstrating the so-called "clothespin effect". This lowers the barriers of syn/anti-isomerization; as a result, protonated molecules with peri-m-tolyl and even peri-(naphthalen-2-yl) substituents exist in crystals as mixtures of rotamers.

Synthesis, structure, and properties of switchable cross-conjugated 1,4-diaryl-1,3-butadiynes based on 1,8-bis(dimethylamino)naphthalene.

A set of novel 1,4-diaryl-1,3-butadiynes terminated by two 7-(arylethynyl)-1,8-bis(dimethylamino)naphthalene fragments was prepared via the Glaser-Hay oxidative dimerization of 2-ethynyl-7-(arylethynyl)-1,8-bis(dimethylamino)naphthalenes. The oligomers synthesized in this way are cross-conjugated systems, in which two conjugation pathways are possible: π-conjugation of 1,8-bis(dimethylamino)naphthalene (DMAN) fragments through a butadiyne linker and a donor-acceptor aryl-C≡C-DMAN conjugation path. The conjugation path can be "switched" simply by protonation of DMAN fragments. X-ray diffraction, UV-vis spectroscopy and cyclic voltammetry are applied to analyze the extent of π-conjugation and the efficiency of particular donor-acceptor conjugation path in these new compounds. X-ray structures and absorption spectra of doubly protonated tetrafluoroborate salts of the oligomers are also discussed.

Neutral Pyrrole Nitrogen Atom as a π- and Mixed n,π-Donor in Hydrogen Bonding.

9-Dimethylaminobenzo[ g]indoles 3-6 and 1-dimethylamino-8-(pyrrolyl-1)naphthalene 7 were examined as possible models for establishing the ability of the pyrrole nitrogen atom to participate in [NHN]+ hydrogen bonding as a proton acceptor. Indoles 3-5 (to a lesser extent 6) form rather stable tetrafluoroborates, with the proton mostly located on the NMe2 group but simultaneously engaged in the formation of a charged intramolecular [NHN]+ hydrogen bond (IHB) with the pyrrole N atom. The theoretically estimated energies of IHB in salts 3H+BF4--6H+BF4- vary between 7.0-10.7 and 6.2-7.0 kcal mol-1 in vapor and MeCN, respectively. The pyrrole N atom undergoes a perceptible pyramidalization but still remains involved in the 6π-electron aromatic system, suggesting that the hydrogen bonding in salts 3H+BF4--6H+BF4- represents a previously unknown mixed NH···N(n,π) interaction. Despite the favorable orientation of the N-H bond and the pyrrole ring in salt 7H+BF4-, no signs of NH···N(n) bonding in it were noticed, and the existing interaction was classified as pure NH···N(π). The results obtained may be useful in studies of secondary protein structures, especially those α-helix sections which contain tryptophan residues.

Multiple transformations of 2-alkynyl-1,8-bis(dimethylamino)naphthalenes into benzo[g]indoles. Pd/Cu-dependent switching of the electrophilic and nucleophilic sites in acetylenic bond and a puzzle of porcelain catalysis.

By means of Sonogashira reaction, a series of 2-alkynyl- and 2,7-dialkynyl derivatives of 1,8-bis(dimethylamino)naphthalene ("proton sponge") have been obtained from the corresponding iodides. It was disclosed that changing the reaction conditions and isolation protocol or conducting the model experiments with the authentic acetylenes results in several types of palladium- and copper-assisted heterocyclizations with the participation of the C≡C bond and 1-NMe2 group. These include: (i) a cyclization into isomeric 1H-benzo[g]indoles with [1,3] migration of the N-methyl group into the newly formed pyrrole ring; (ii) a similar cyclization with a loss of the methyl group; (iii) a tandem process of cyclization into benzo[g]indoles and their subsequent 3,3'-dimerization; and (iv) a copper-catalyzed oxidative transformation into 3-aroylbenzo[g]indoles. In most cases, the reactions occur in parallel, but under certain conditions, one of the above products becomes predominant or even the only one. Remarkably, in Pd-catalyzed cyclizations i-iii, the acetylenic bond behaves as an electrophile being attacked at the ß-position by the amine nitrogen atom. In contrast, in transformation iv, the C≡C bond attacks by its Cα atom on the aminomethyl radical functionality N(Me)-CH2· presumably arising at copper oxidation/deprotonation of the 1-NMe2 group. Studying rearrangement i, some evidence for the porcelain catalysis was obtained.

The Benefits of Family Screening in Rare Diseases: Genetic Testing Reveals 165 New Cases of Fabry Disease among At-Risk Family Members of 83 Index Patients.

BACKGROUND: Fabry disease (FD, OMIM #301500) is a rare, progressive, X-linked, inherited genetic disease caused by a functional deficiency of lysosomal α-galactosidase, leading to the accumulation of glycosphingolipids in virtually all of the body's cell types and fluids. Patients with rare genetic diseases and non-specific symptoms often experience substantial diagnostic delays, which can negatively impact the prompt initiation of treatment. If FD is not treated specifically, end organ damage (such as chronic renal failure, hypertrophic cardiomyopathy with arrhythmia, and strokes) impairs quality of life and reduces life expectancy. PATIENTS AND METHODS: For 83 consecutive patients with FD referred to the Russian reference center for lysosomal storage diseases, family trees were built and genetic testing (cascade genotyping) was offered to family members. RESULTS: The pathogenic GLA variant associated with FD was identified for all 83 probands. Family testing using cascade genotyping enabled the identification of 165 additional cases of FD among the tested 331 at-risk family members. DISCUSSION: This is the first study to have described family screening in a large Russian cohort of patients with FD and chronic kidney disease. Raising awareness of FD among clinicians is important for earlier diagnosis and specific treatment.

Magnetic therapy in acute and subacute non-specific back pain: Results of an open multicenter study.

Magnetic therapy (MT) is a non-drug method that improves the effectiveness of treatment of musculoskeletal pain, including:acute non-specific back pain (NBP). Objective of our study was to evaluate the results of complex treatment of patients with acute/subacute NBP at home using MT. The study group consisted of 339 patients with severe acute/subacute NBP. All patients received nonsteroidal anti-inflammatory drugs (NSAIDs). 166 patients (Group 1) received a course of MT (ALMAG+ device), 173 patients or a control group (Group 2) who did not receive MT. The dynamics of pain was significantly higher in group 1 than in group 2. So, the intensity of pain during movement (NRS) decreased from 7 [5;8] and 7 [5;8] to 0 [0;13] and 2 [1;3] after 1 month. (p<0.001). Significant differences between Groups 1 and 2 were observed in the dynamics of pain at rest and at night, overall health assessment (OHA), and sleep function and disorders. The average duration of NSAIDs use in Group 1 was 8.8±3.9, Group 2 - 11.8±5.7 days (p<0.001). The use of MT increases the effectiveness of treatment of acute/subacute NBP and reduces the need for NSAIDs use.

Method of delivery and pregnancy outcomes in Asia: the WHO global survey on maternal and perinatal health 2007-08.

BACKGROUND: There has been concern about rising rates of caesarean section worldwide. This Article reports the third phase of the WHO global survey, which aimed to estimate the rate of different methods of delivery and to examine the relation between method of delivery and maternal and perinatal outcomes in selected facilities in Africa and Latin America in 2004-05, and in Asia in 2007-08. METHODS: Nine countries participated in the Asia global survey: Cambodia, China, India, Japan, Nepal, Philippines, Sri Lanka, Thailand, and Vietnam. In each country, the capital city and two other regions or provinces were randomly selected. We studied all women admitted for delivery during 3 months in institutions with 6000 or fewer expected deliveries per year and during 2 months in those with more than 6000 deliveries. We gathered data for institutions to obtain a detailed description of the health facility and its resources for obstetric care. We obtained data from women's medical records to summarise obstetric and perinatal events. FINDINGS: We obtained data for 109 101 of 112 152 deliveries reported in 122 recruited facilities (97% coverage), and analysed 107 950 deliveries. The overall rate of caesarean section was 27.3% (n=29 428) and of operative vaginal delivery was 3.2% (n=3465). Risk of maternal mortality and morbidity index (at least one of: maternal mortality, admission to intensive care unit [ICU], blood transfusion, hysterectomy, or internal iliac artery ligation) was increased for operative vaginal delivery (adjusted odds ratio 2.1, 95% CI 1.7-2.6) and all types of caesarean section (antepartum without indication 2.7, 1.4-5.5; antepartum with indication 10.6, 9.3-12.0; intrapartum without indication 14.2, 9.8-20.7; intrapartum with indication 14.5, 13.2-16.0). For breech presentation, caesarean section, either antepartum (0.2, 0.1-0.3) or intrapartum (0.3, 0.2-0.4), was associated with improved perinatal outcomes, but also with increased risk of stay in neonatal ICU (2.0, 1.1-3.6; and 2.1, 1.2-3.7, respectively). INTERPRETATION: To improve maternal and perinatal outcomes, caesarean section should be done only when there is a medical indication. FUNDING: US Agency for International Development (USAID); UNDP/UNFPA/WHO/World Bank Special Programme of Research, Development and Research Training in Human Reproduction (HRP), WHO, Switzerland; Ministry of Health, Labour and Welfare of Japan; Ministry of Public Health, China; and Indian Council of Medical Research.

Understanding the Mechanism of SiC Plasma-Enhanced Chemical Vapor Deposition (PECVD) and Developing Routes toward SiC Atomic Layer Deposition (ALD) with Density Functional Theory.

Understanding the mechanism of SiC chemical vapor deposition (CVD) is an important step in investigating the routes toward future atomic layer deposition (ALD) of SiC. The energetics of various silicon and carbon precursors reacting with bare and H-terminated 3C-SiC (011) are analyzed using ab initio density functional theory (DFT). Bare SiC is found to be reactive to silicon and carbon precursors, while H-terminated SiC is found to be not reactive with these precursors at 0 K. Furthermore, the reaction pathways of silane plasma fragments SiH3 and SiH2 are calculated along with the energetics for the methane plasma fragments CH3 and CH2. SiH3 and SiH2 fragments follow different mechanisms toward Si growth, of which the SiH3 mechanism is found to be more thermodynamically favorable. Moreover, both of the fragments were found to show selectivity toward the Si-H bond and not C-H bond of the surface. On the basis of this, a selective Si deposition process is suggested for silicon versus carbon-doped silicon oxide surfaces.

A guide to acquired vitamin K coagulophathy diagnosis and treatment: the Russian perspective.

Physicians often come across with cases of vitamin K antagonists-dependent coagulopathy for reasons such as accidental use of the vitamin K antagonists (VKA), excessive administration of prescribed anticoagulants of indirect action or not reported administration of vitamin K antagonists due to memory impairment and/or other mental disorders, even deliberate use thereof (attempt to murder or suicide). Rodenticide-poisoning (coumarins, warfarins) via food or occupational accidents are difficult to diagnose. This article discusses different types of acquired vitamin K-dependent coagulopathy. Differential diagnosis is primarily based on patient statements before additional causes of vitamin K deficiency are explored. Even when pathological vitamin K deficiency is not determined, appropriate and urgent medical treatment is necessary: administration of fresh frozen plasma or concentrated factors of the prothrombin complex, administration of vitamin K remedies along with symptomatic therapy. With early diagnosis and prescription of appropriate therapy, prognosis is favorable. Reasons for vitamin K antagonists-dependent coagulopathy cases.

Modeling Mechanism and Growth Reactions for New Nanofabrication Processes by Atomic Layer Deposition.

Recent progress in the simulation of the chemistry of atomic layer deposition (ALD) is presented for technologically important materials such as alumina, silica, and copper metal. Self-limiting chemisorption of precursors onto substrates is studied using density functional theory so as to determine reaction pathways and aid process development. The main challenges for the future of ALD modeling are outlined.