Constituents Of Compounds Research Articles

Asymmetric Syntheses of All Stereoisomers of 3-Hydroxyproline; A Constituent of Several Bioactive Compounds

Synthesis of an unusual β-hydroxy-α-amino acid, 3-hydroxyproline, and its derivatives have been achieved enantioselectively by employing Sharpless asymmetric epoxidation and reductive cyclization as the key steps.

Structural Determinants of the β-Selectivity of a Bacterial Aminotransferase

Chiral β-amino acids occur as constituents of various natural and synthetic compounds with potentially useful bioactivities. The pyridoxal 5'-phosphate (PLP)-dependent S-selective transaminase from Mesorhizobium sp. strain LUK (MesAT) is a fold type I aminotransferase that can be used for the preparation of enantiopure β-Phe and derivatives thereof. Using x-ray crystallography, we solved structures of MesAT in complex with (S)-β-Phe, (R)-3-amino-5-methylhexanoic acid, 2-oxoglutarate, and the inhibitor 2-aminooxyacetic acid, which allowed us to unveil the molecular basis of the amino acid specificity and enantioselectivity of this enzyme. The binding pocket of the side chain of a β-amino acid is located on the 3'-oxygen side of the PLP cofactor. The same binding pocket is utilized by MesAT to bind the α-carboxylate group of an α-amino acid. A β-amino acid thus binds in a reverse orientation in the active site of MesAT compared with an α-amino acid. Such a binding mode has not been reported before for any PLP-dependent aminotransferase and shows that the active site of MesAT has specifically evolved to accommodate both β- and α-amino acids.

Latin compounds

Abstract This paper intends to offer a descriptive survey of compounding in Latin, updated with the findings of the most recent literature. In the first part it focuses on the nature of basic constituents of Latin compounds and on the differentiation between compounds and other kinds of constructions involving two or more constituents, such as (parasynthetic) derivatives and free phrases. In the second part the core patterns of Latin compounds are exemplified, focusing on Nominal and Verbal Compounding, and a classification according to formal and semantic characteristics is proposed. Finally conclusions are drawn, the results of the investigation summarized, and some useful questions for future research are highlighted.

Phytotoxic effects of essential oil from Cymbopogon citratus and its physiological mechanisms on barnyardgrass (Echinochloa crus-galli)

Lemongrass (Cymbopogon citratus) essential oil was identified by GC–MS for their major compound constituents; six compounds representing 92.59% of the total essential oil were identified. The main constituent was citral (76.00%). In a laboratory bioassay, high concentration of essential oil significantly inhibited germination and seedling growth of Echinochloa crus-galli and affecting α-amylase activity of seeds. In a glass house bioassay, essential oil at concentrations of 1.25, 2.5, 5 and 10% (v/v) was foliar-applied on E. crus-galli at 28 days after sowing at spray volume of 1000Lha−1. Observation of leaf wilt symptoms was noted at 6h after treatment. Chlorophyll a, b and carotenoid content was decreased with concentrations of essential oil, indicating that essential oil interferes with photosynthetic metabolism. C. citratus essential oil caused an electrolyte leakage indicating membrane disruption and loss of integrity. Treated leaves exhibited an increase in thiobarbituric acid reactive substances (TBARS), suggesting lipid peroxidation. It is to conclude that essential oil is phytotoxic and could be utilized as a natural herbicide for future weed control.

ChemInform Abstract: A Convenient Approach for the Synthesis of Imidazole Derivatives Using Microwaves

AbstractReview: 90 refs.

Understanding the mental lexicon through neglect dyslexia: a study on compound noun reading

The present study employs neglect dyslexia (ND) as an experimental model to study compound-word processing; in particular, it investigates whether compound constituents are hierarchically organized at mental level and addresses the possibility of whole-word representation. Seven Italian-speaking patients suffering from ND participated in a word naming task. Both left-headed (pescespada, swordfish) and right-headed (astronave, spaceship) Italian compound nouns were used as stimuli. Non-existent compounds, which were generated by substituting the leftmost constituent of a compound with an orthographically similar word (e.g., *pestespada, *plaguesword), were also employed. A significant headedness effect emerged in the group analysis: patients read left-headed compounds better than right-headed compounds. A significant lexicality effect was also found: the participants read real compounds better than their non-existent compound pairs. Moreover, logit mixed-effects analyses indicated a left-hand constituent frequency effect. Results are discussed in terms of hierarchical representation of compounds and direct access to compound lemma nodes.

ChemInform Abstract: Benzimidazole: A Medicinally Important Heterocyclic Moiety

AbstractReview: 50 refs.

The Potential Role of Quercus Infectoria Gall Extract on Osteoblast Function and Bone Metabolism

The galls of the Quercus infectoria (QI) tree are traditionally believed to have great medicinal value. Pharmacologically the galls are claimed to have various biological activities such as astringent effect, antidiabetic, antitremorine, local anaesthetic, antipyretic, anti-inflammatory, antibacterial, antiviral and many more. These pharmacological activities of gall extracts were reported to be due to its excellent antioxidant activity with phytochemicals constituents of phenolic and flavanoid compounds. The phenolic compounds or polyphenols can act on bone metabolism by modulating osteoblast proliferation, differentiation and mineralization, as well as osteoclastogenesis. In addition, elemental and physico-chemical analysis indicated the presence of important minerals in QI, such as calcium, magnesium, phosphorus, oxygen, potassium, aluminium, carbon, zinc, iron, manganese, nickel and silica. The current review will be focusing on the potential bone health benefits of the well-known traditional herbal medicine, QI or locally known as the “manjakani”.

Effect of Tulsi ( Ocimum sanctum Linn.) on Clinical and Biochemical Parameters of Metabolic Syndrome

Metabolic syndrome can be defined as a set of symptoms, associated with a risk of coronary artery disease, hypertension, hyperlipidemia, hyperglycemia and obesity. Eugenol is a phenolic compound and major constituent of essential oils extracted from different parts of Tulsi plant. Its therapeutic use has been established on the basis of several pharmacological studies related with hyperglycemia, hypertension and dyslipidemia. To investigate the effect of Tulsi on clinical and biochemical parameters of metabolic syndrome. Hundred patients randomly selected for this study, further categorized in 2 groups, control group and study group. Patients were asked to take 5ml of Tulsi extract two times a day for three months. Baseline parameters were taken for every patient i.e. BMI, W/H Ratio fasting blood sugar, blood pressure, HbA1c, lipid profile. Biochemical and anthropometric data were also recorded at the end of the study. On comparing control and study population for effect of Tulsi therapy, an improving trend was observed in study group.BMI (27.00±3.23 to 27.10±8.64 kg/m 2 , p<0.9), SBP (151.30±8.48 to 138.68±9.84 mmHg, p<0.001), DBP (95.76±3.63 to 87.12±8.81 mmHg, p<0.001), glycemic control - FBS (209.26±40.15 to 155.28±20.70 mg/dl, p<0.001), HbA1c (8.82±1.25 to 7.34±0.89%, p<0.001). Lipid profile-total cholesterol (244.04±26.30 to 209.28±29.03mg/dl, p<0.001), triglyceride (176.48±16.75 to 138.32±15.17mg/dl, p<0.001), HDL (33.58±3.47 to 39.36±4.25mg/dl, p<0.001), LDL (174.9±26.82 to 142.11±27.50mg/dl, p<0.001), VLDL (35.37±3.84 to 27.66±3.03mg/dl, p<0.001). In metabolic syndrome, Tulsi therapy significantly reduces blood glucose, blood pressure and lipid profile. It shows the therapeutic effect of Tulsi and it may be used as an adjunct with diet and drugs in management of metabolic syndrome.

Evidence for morphological composition at the form level in speech production

We investigated in two picture–word-interference experiments whether there is evidence for composition during compound production (Experiment 1). In Experiment 2, we tried to determine the level at which composition takes place. In Experiment 1, shared morphemes between distractor and target (HANDTASCHE, handbag) sped up naming regardless of category membership: semantically opaque (Plaudertasche, chatterbox) and semantically transparent distractors (Reisetasche, travelling bag) facilitated picture naming to a comparable degree. In Experiment 2, targets (BROTMESSER, bread knife) were combined with a simple word distractor (Kuchen, cake) categorically related to a target compound constituent but not related to the compound as a whole. This target was further paired with a categorically related compound distractor (Kochlöffel, wooden spoon). The simple word distractor was also paired with a categorically related compound constituent (BROT, bread). Whenever distractor (e.g., Kochlöffel, Kuchen) and target (BROTMESSER, BROT, respectively) were categorically related, semantic inhibition was observed. Distractors (e.g., Kuchen) related to only one compound constituent did not affect compound production. Taken together, our results indicate that during compound production a single lemma node is activated and that morphological composition takes place at the form level of representation. Current lexical selection mechanisms in language production models are not supported by these data.

The tide predictions for D-Day

Based on the physics of Newton and Laplace, the big brass tide-predicting machine designed by Lord Kelvin was crucial for the success of the Normandy invasion in World War II.

Chemical Composition of Essential Oils from Ripe and Unripe Fruits of Piper amalago L. var. medium (Jacq.) Yunck and Piper hispidum Sw.

The chemical composition of essential oils from unripe and ripe fruits of Piper amalago L. var. medium (Jacq.) Yunck and Piper hispidum Sw. was examined using GC/MS analysis. The analysis of oils from P. amalago revealed a predominance of oxygenated sesquiterpenes and 65 compounds were identified; their main constituents are: (E)- nerolidol (14.2% and 19.9%), germacrene-D-4-ol (10.3% and 12.7%), α-cadinol (11.1% and 8.2%) in 99.6% and 98.7% of the compounds for unripe and ripe fruits, respectively. Piper hispidum revealed a predominance of sesquiterpene hydrocarbons, from which we identified 53 compounds including: α-copaene (28.7% and 36.2%), α-pinene (13.9% and 7.1%), α-pinene (13.3% and 7.5%), and (E)-nerolidol (2.9% and 7.0%) which represented 97.8% and 98.1% of the compound constituents for unripe and ripe fruits, respectively. The essential oils of fruits of P. amalago and P. hispidum are reported for the first time.

Benefits and costs of lexical decomposition and semantic integration during the processing of transparent and opaque English compounds

Six lexical decision experiments were conducted to examine the influence of complex structure on the processing speed of English compounds. All experiments revealed that semantically transparent compounds (e.g., rosebud) were processed more quickly than matched monomorphemic words (e.g., giraffe). Opaque compounds (e.g., hogwash) were also processed more quickly than monomorphemic words. However, when the experimental materials and/or procedure encouraged decomposition/integration, this advantage disappeared. This research suggests that morphological decomposition initiated by the existence of complex structure results in the availability of both the lexical and semantic representations of compound constituents, regardless of whether the compounds are transparent or opaque, and that meaning composition is attempted. This meaning composition further speeds up transparent compound processing beyond lexical facilitation but slows down opaque compound processing because the computed meaning for opaque compounds conflicts with the retrieved meaning.

Pressurized liquid extraction of ginger ( Zingiber officinale Roscoe) with bioethanol: An efficient and sustainable approach

To develop an efficient green extraction approach for recovery of bioactive compounds from natural plants, we examined the potential of pressurized liquid extraction (PLE) of ginger ( Zingiber officinale Roscoe) with bioethanol/water as solvents. The advantages of PLE over other extraction approaches, in addition to reduced time/solvent cost, the extract of PLE showed a distinct constituent profile from that of Soxhlet extraction, with significantly improved recovery of diarylheptanoids, etc. Among the pure solvents tested for PLE, bioethanol yield the highest efficiency for recovering most constituents of gingerol-related compounds; while for a broad concentration spectrum of ethanol aqueous solutions, 70% ethanol gave the best performance in terms of yield of total extract, complete constituent profile and recovery of most gingerol-related components. PLE with 70% bioethanol operated at 1500 psi and 100 °C for 20 min (static extraction time: 5 min) is recommended as optimized extraction conditions, achieving 106.8%, 109.3% and 108.0% yield of [6]-, [8]- and [10]-gingerol relative to the yield of corresponding constituent obtained by 8 h Soxhlet extraction (absolute ethanol as extraction solvent).

A -fi végű magyar családnevek típusai és története

This paper presents the types, the history and some related problems of surnames including the element -fi (‘son of’), originally a posterior constituent of compounds, which developed into a derivative suffix producing surnames in Hungarian. This surname type has not been discussed frequently in the literature, so its comprehensive survey, which reconsiders earlier remarks as well, is justifiable. The author examines the role of the relevant family names among the Hungarian historical surnames that have evolved naturally; among the artificial surnames formed in the 19th–20th centuries in the process of official name changes; and among contemporary surnames. Characteristics and relations of these different layers of the Hungarian surname stock are explored by analysing statistics based on some large corpora of representative value. The author also searches for explanations behind the observed differences. The paper examines the origins, the development and the possible changes of this name type, identifying many influential background features in language, name and cultural history. The author presents the occurrence and the frequency of the name type and its important representatives, taking name geographical, temporal and social factors into consideration. Relations to other name types as well as to surnames seemingly ending in -fi are also treated. By elaborating a comprehensive approach to this type of surname structure, the author wishes to point out the importance and efficiency of the separate and joint examinations of the different layers of the surname stock.

Benzimidazole: a medicinally important heterocyclic moiety

Benzimidazole nucleus is a constituent of many bioactive heterocyclic compounds that are of wide interest because of their diverse biological and clinical applications. Moreover, benzimidazole derivatives are structural isosters of naturally occurring nucleotides, which allows them to interact easily with the biopolymers of the living system. This created interest in researchers who have synthesized variety of benzimidazole derivatives and screened them for their various biological activities, viz., anticancer, hormone antagonist, antiviral, anti-HIV, anthelmintic, antiprotozoal, antimycobacterial, antihypertensive, anti-inflammatory, analgesic, anxiolytic, antiallergic, coagulant, anticoagulant, antioxidant as well antidiabetic activities.

Biological importance of imidazole nucleus in the new millennium

Imidazole nucleus is a constituent of many bioactive heterocyclic compounds that are of wide interest because of their diverse biological and clinical applications. This created interest in researchers to synthesize variety of imidazole derivatives and to screen them for their various biological activities viz. anti-cancer, anti-viral, antiHIV, anti-protozoal, anti-mycobacterial, anti-inflammatory, analgesic, anxiolytic, as well anti-diabetic activities.

Ozonolysis of α-PINENE, β-PINENE, d- and l-Turpentine Oil Studied by Chirooptical Methods; Some Implications on the Atmospheric Chemistry of Biogenic Volatile Organic Compounds

The main constituents of biogenic volatile organic compounds (BVOC) released in the atmosphere from vegetation are terpenes. The most common terpenes are α-pinene and β-pinene. These molecules react with ozone, forming oxidized derivatives which have low vapor pressure and which nucleate into secondary organic aerosol (SOA). Such aerosol-forming reactions have been simulated in the gas phase on laboratory scale with the visualization of the formation of SOA. Electronic absorption spectroscopy shows that the UV peak of pinenes at 205 nm is shifted to 225 nm during and after ozonolysis and is accompanied by a series of spectral features in the near infrared region (between 850 nm and 1100 nm). Optical rotatory dispersion (ORD) spectra were recorded on pure β(+)pinene and β(−)pinene. After ozonolysis β-pinene enantiomers are converted into nopinone enantiomers. The ORD spectra of both (−)nopinone and (+)nopinone respectively were recorded. The former showed a peak at 453 nm, an inflection point at 430 nm and a trough at 405 nm. The ORD spectrum of (−)-nopinone appears completely symmetrical to that of (+)nopinone. Thus, ORD spectroscopy can distinguish between BVOC and oxidized BVOC quite easily at least in the case of β-pinene. The ORD spectra of α-pinene enantiomers are different from those of β-pinene enantiomers and although the ORD spectra of ozonized α-pinene are not easily distinguishable from those of the primary compounds, they are completely different from those of ozonized β-pinene enantiomers. A reasonable natural model of BVOC is offered by l- and d-turpentine oil whose composition reflects that of the BVOC from conifer forests. The ORD spectra of ozonized l- and d-turpentine has permitted to distinguish between the levorotatory and dextrorotatory oxidation products and showing the ketone peak at about 367–380 nm, thus permitting in a real model to distinguish between primary BVOC (turpentine) and oxidized BVOC (or SOA) corresponding to ozonized turpentine. It has been proposed that ORD spectra in the gas phase could be used to detect chiral BVOC and oxidized chiral BVOC.

Some Further Observations on the Spelling of English Compounds

This paper explores the main factors which determine the spelling of English N+N compounds. On the basis of a corpus extracted from LDCE (2000) and LDCE (2003), I discuss the following factors, which may have an influence on the spelling of English N+N compounds: the number of syllables, the morphological structure of the first constituent of compounds and the nature of phonotactic transition at the morpheme boundary. The analysis shows that the first two factors exert major influences on the spelling of compounds, while the influence of the third factor varies depending on the number of syllables. In the examined corpus, very few compounds with more than four syllables are spelled solid. The majority of two-syllable compounds are spelled solid under all circumstances, while only 74 four-syllable compounds are spelled solid. The highest percentage of two-syllable compounds are spelled open (49.7%) if the first constituent ending in a consonant builds a consonant cluster at the morpheme boundary. The majority of three-syllable compounds are spelled open unless the first constituent ends in a schwa. The proposed analysis of the extracted corpus shows varied influence of different factors and enables us to establish their partial ranking.

One-pot synthesis of tetrahydrobenzofuran-3-carboxylates

Benzofuran cycle is constituent of some natural compounds and drugs [1–3]. In particular, tetrahydrobenzofuran fragment contributes to the composition of sesquiterpenoids ligularone and isoligularone [4], and benzodihydrofuran system is present in the molecules of such antifungal antibiotics as griseofulvin and sodium usninate [5]. We developed a convenient one-pot approach to tetrahydrobenzofuran series representatives II and III on the basis of condensation of methyl-3-bromo-3nitroacrylate I with cyclic β-diketones: dihydroresorcin and dimedone. Reaction proceeds at reflux of equimolar amounts of reagents in methanol in the presense of potassium acetate. DOI: 10.1134/S1070363210050361