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CyBase is a curated database and information source for backbone-cyclized proteins. The database incorporates naturally occurring cyclic proteins as well as synthetic derivatives, grafted analogues and acyclic permutants. The database provides a centralized repository of information on all aspects of cyclic protein biology and addresses issues pertaining to the management and searching of topologically circular sequences. The database is freely available at http://research.imb.uq.edu.au/cybase.

Covering: 2000 to 2004 Lignans are a class of secondary plant metabolites produced by oxidative dimerization of two phenylpropanoid units. Although their molecular backbone consists only of two phenylpropane (C6–C3) units, lignans show an enormous structural diversity. There is a growing interest in lignans and their synthetic derivatives due to applications in cancer chemotherapy and various other pharmacological effects. This review deals with lignans possessing anticancer, antioxidant, antimicrobial, anti-inflammatory and immunosuppressive activities, and comprises the data reported in more than 100 peer-reviewed articles, so as to highlight the recently reported bioactive lignans that could be a first step towards the development of potential new therapeutic agents.

An overview mapping recent trends in the determination of polyphenols of natural origin (mostly flavonoids) and their synthetic derivatives by electromigration methods is presented. The overview (covering the period of the recent 5 years and comprising 61 references) is focused on capillary zone electrophoresis (CZE) and micellar electrokinetic chromatography (MEKC) with various detection methods. Techniques comprising on-line pre-separation such as isotachophoresis (ITP)-CZE and flow-injection-CZE, chiral separations and CZE evaluation of antioxidation activity are also discussed.

Islet-Brain (IB) proteins [also called JNK-interacting proteins (JIPs)] are scaffold proteins that are mainly expressed in the pancreatic islets and in the brain. Functionally, the IB family is composed of IB1, IB2, IB3, and IB4 each with distinct splice variants. The IB family of proteins regulates several mitogen-activated protein kinase (MAPK) pathways by tethering their components and modifying the spectrum of substrates targeted by the MAPKs. The expression of these proteins is developmentally regulated, indicating that they play important functions during brain formation. While it is currently unclear what the precise physiological functions of the IB proteins are, there are indications that they participate in subcellular targeting of signalling proteins and modulate cell survival. Synthetic derivatives of these proteins can efficiently counteract apoptotic signalling in cells and tissues and represent therefore promising protective agents against traumatic insults, including stroke and hypoxia. This review will focus on the molecular functions of the IB proteins and their potential implications in the development of several human pathologies.

The potent anti-inflammatory pharmacologic effects of the corticosteroids (cortisone and synthetic derivatives) has led to their extensive usage in the management of rheumatologic diseases and athletic musculoskeletal injuries. The efficacy and risks of locally injected or systemically administered corticosteroids in the treatment of athletic injuries are unclear.To review critically the medical literature and determine complications and risks associated with corticosteroid treatment of athletic injuries.A search of 3 databases-MEDLINE, CINAHL, and Cochrane Clinical Trial Register-was performed using the OVID interface for all years between 1966 and 2003. The search first combined all references under the medical subject headings adrenal cortex hormones, glucocorticoids, and glucocorticoids, synthetic. A second search combined all references under the medical subject headings athletic injuries, sprains and strains, tendon injuries, shoulder injuries, rotator cuff disease, tennis elbow, and lateral epicondylitis. The references identified by these 2 searches were intersected and limited to human only to produce 130 articles. Relevant review articles were scanned, references reviewed, and additional articles retrieved for consideration of inclusion.For inclusion in this critical review, articles must meet the following criteria: (1) subjects were human, (2) subjects had athletic-related injuries, and (3) subjects received corticosteroid treatment. Ultimately, 43 studies met inclusion criteria.Selected articles were then categorized as to whether the primary focus was usage/efficacy of corticosteroid injection therapy, occurrence of complications of corticosteroid injection therapy, or usage or complications of systemic corticosteroid therapy.Twenty-five selected studies primarily examined the usage/efficacy of corticosteroid injections in the treatment of various athletic injuries. Of the 983 total subjects who received corticosteroid injections among these studies, only minor complications of treatment were reported. Eighteen selected studies primarily described complications of corticosteroid injections in the treatment of athletic injuries. Of these, tendon and fascial ruptures were the predominant complications reported. The search identified no articles that addressed the usage of or complications of systemic corticosteroids in the treatment of athletic injuries, although tibial stress fracture and multifocal osteonecrosis occurred in individuals being treated for nonathletic injury conditions.This critical review reveals that the existing medical literature does not provide precise estimates for complication rates following the therapeutic use of injected or systemic corticosteroids in the treatment of athletic injuries. Tendon and fascial ruptures are often reported complications of injected corticosteroids, whereas tibial stress fractures and multifocal osteonecrosis were described with systemic corticosteroids.

A new cytotoxic steroidal alkaloid, plakinamine I, with an unprecedented 3α-amino-19-acetoxy nucleus was isolated from a Corticium sp. sponge. The structure has been elucidated by spectroscopic analysis and secured by the synthesis of the model 19-acetoxy-3α-aminocholestane. The evaluation of the cytotoxic activities of several synthetic derivatives, intermediates of the above synthesis, allowed us to explore the influence of the different functions on the cytotoxicity observed for natural plakinamine I. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)

We describe herein an evaluation of trypanocidal effects of the natural alkaloid piperine and twelve synthetic derivatives against epimastigote and amastigote forms of the protozoan parasite Trypanosoma cruzi, the causative agent of the incurable human disease, Chagas' disease. The results obtained point to piperine as a suitable template for the development of new drugs with trypanocidal activity.

The synthesis is described of a [D-Ala2]-deltorphin I peptoid analogue in which all amino acid residues have been substituted by the corresponding N-alkylglycine residues. The [D-Ala2]-deltorphin I retropeptoid was also prepared as well as [Ala1,D-Ala2]-deltorphin 1 and the corresponding peptoid. Structural investigations by FT-IR and fluorescence measurements were carried out on the synthetic analogues and on some [D-Ala2]-deltorphin 1 peptide–peptoid hybrids previously prepared. According to the fluorescence measurements the distance between the aromatic residues in the deltorphin I peptoid and retropeptoid is similar to that suggested for the δ- and µ-opioids, respectively. Measurements of CD in the presence of β-cyclodextrin, and some preliminary pharmacological experiments were also performed. No dichroic bands are present in the spectrum of the [Ntyr1,D-Ala2]-deltorphin I, but an increasing dichroic effect appears in the spectra of both the deltorphin I peptoid and retropeptoid. Activity tests on isolated organ preparations showed that the modifications made produced a dramatic decrease in the agonistic activity of the synthetic derivatives. Copyright © 2004 European Peptide Society and John Wiley & Sons, Ltd.

Unambiguous and complete assignments of 1H and 13C NMR chemical shifts for 14 19-nor-neoclerodane diterpenoids, nine of them isolated from natural sources and five other synthetic derivatives, are presented. The assignments are based on 2D shift-correlated (1H,1H-COSY, 1H,13C-gHSQC and 1H,13C-gHMBC) and NOE experiments. The conformations of rings A and B of these compounds are supported by the 3J(H,H) values and they agreewith the low-energy conformations obtained by semi-empirical calculations. Moreover, the data obtained in thiswork for 2-acetoxyteucvidin and a semisynthetic 18-aldehyde derivative indicate that the configuration at C-2 of the former and at C-10 of the latter must be reversed with respect to those reported previously., The authors are indebted to Miss M. D. Casado and Mrs M. Plaza, Centro de Qu´ımica Org´anica ‘Manuel Lora-Tamayo’, CSIC, Madrid, for technical assistance. This work was supported by funds from the Comisi´on Asesora de Investigaci ´on Cient´ıfica y T´ecnica (CAICYT), grant No. AGL 2001-1652-C02-01, and the Direcci ´on General de Investigaci´on Cient´ıfica y T´ecnica (DGICYT), grant No. BQU 2000- 0868.

Breast cancer still remains a major problem in its incidence, morbidity and mortality; therefore, more effective strategies for its prevention are urgently needed. Retinoids, natural and synthetic derivatives of vitamin A, possess antiproliferative and proapoptotic properties, making them a promising class of chemopreventive agents against breast cancer. The efficacy of all-trans retinoic acid, 9-cis-retinoic acid, LGD1069 (Targretin, bexarotene), and N-(4-hydroxyphenyl)retinamide (fenretinide) as breast cancer chemopreventive agents is being studied. A better understanding of the molecular mechanisms of action of these agents should lead to improvements in their clinical application. In this review, we discuss the mechanisms by which retinoids exert their antiproliferative and apoptotic effects in breast cancer cells.

Molecular self-assembly is central to many processes in both biology and supramolecular chemistry. The G-quartet, a hydrogen-bonded macrocycle formed by cation-templated assembly of guanosine, was first identified in 1962 as the basis for the aggregation of 5'-guanosine monophosphate. We now know that many nucleosides, oligonucleotides, and synthetic derivatives form a rich array of functional G-quartets. The G-quartet surfaces in areas ranging from structural biology and medicinal chemistry to supramolecular chemistry and nanotechnology. This Review integrates and summarizes knowledge gained from these different areas, with emphasis on G-quartet structure, function, and molecular recognition.

The retinoids—natural and synthetic derivatives of vitamin A—play a role in cancer therapy and prevention. Their role in chemoprevention has been highlighted through the results of clinical and epidemiological studies in conjunction with basic research on retinoid mechanisms of action, advances in genomic information, novel organic synthesis of retinoid analogs, and availability of reliable model systems. This chapter focuses on the results of recent retinoid clinical cancer therapy and chemoprevention trials, reviews the current understanding of the molecular mechanism of retinoid action, discusses in vitro models used to study retinoid chemoprevention, and summarizes information on retinoid target genes. An understanding of the convergence of clinical and basic scientific advances in the retinoid field should lead to improved strategies to use these pharmacological agents in cancer therapy or chemoprevention.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:48:30Z No. of bitstreams: 1 S0100-40422003000300017.pdf: 1235353 bytes, checksum: 513c5a0ee8b7bfde18670b97d46b04d2 (MD5) Made available in DSpace on 2013-08-22T18:48:30Z (GMT). No. of bitstreams: 1 S0100-40422003000300017.pdf: 1235353 bytes, checksum: 513c5a0ee8b7bfde18670b97d46b04d2 (MD5) Previous issue date: 2003-05-01 Made available in DSpace on 2013-09-30T19:38:27Z (GMT). No. of bitstreams: 2 S0100-40422003000300017.pdf: 1235353 bytes, checksum: 513c5a0ee8b7bfde18670b97d46b04d2 (MD5) S0100-40422003000300017.pdf.txt: 48210 bytes, checksum: 3e67fd5abbd61573874a7446f3c79476 (MD5) Previous issue date: 2003-05-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T15:10:19Z No. of bitstreams: 2 S0100-40422003000300017.pdf: 1235353 bytes, checksum: 513c5a0ee8b7bfde18670b97d46b04d2 (MD5) S0100-40422003000300017.pdf.txt: 48210 bytes, checksum: 3e67fd5abbd61573874a7446f3c79476 (MD5) Made available in DSpace on 2014-05-20T15:10:19Z (GMT). No. of bitstreams: 2 S0100-40422003000300017.pdf: 1235353 bytes, checksum: 513c5a0ee8b7bfde18670b97d46b04d2 (MD5) S0100-40422003000300017.pdf.txt: 48210 bytes, checksum: 3e67fd5abbd61573874a7446f3c79476 (MD5) Previous issue date: 2003-05-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Many substances from different sources have been used by men for decades to control insects. After the 2nd World War, the use of inorganic compounds have declined drastically and natural products, as well as synthetic derivatives, have been widely used instead. The search for natural alternatives have improved the development of bench top bioassays and an array of synthetic approaches for known and novel natural products that shows relevant activities as feeding supressors and deterrents. The studies concerning mode of action and environmental impact of these substances, that may be biodegradable and selective for undesired insects, had led to the evaluation and discovery of a number of molecules, mostly terpenoids and alkaloids, that are well reported as candidates for inseticidal compounds that could be an effective alternative for insects control with a lower impact on human health, household animals and the environment. Universidade Estadual Paulista Júlio de Mesquita Filho Instituto de Química Universidade Estadual Paulista Júlio de Mesquita Filho Instituto de Química

Publisher Summary Cyclodextrins (CyDs) were first isolated as degradation products of starch and were characterized as cyclic oligosaccharides. This chapter deals with some aspects of the utilization of chemically modified CyDs in pharmaceutical formulations and discusses some fundamental characteristics of CyDs, which should be considered in the development of advanced dosage forms. Some physicochemical and biological profiles of CyD derivatives are briefly described, comparing them with those of natural CyDs. An important characteristic of CyDs is the formation of inclusion complexes in both the solution and solid states, in which each guest molecule is surrounded by the hydrophobic environment of the CyDs cavity. This can lead to the alteration of physicochemical properties of guest molecules, and can eventually have considerable pharmaceutical potential. Many solid compounds are known to exist in different crystalline modifications such as amorphous, crystalline or glassy states; affecting solubility, dissolution rate, stability, and bioavailability. The natural CyDs and their synthetic derivatives have successfully been applied to improve undesirable drug properties such as solubility, stability or bioavailability. In addition, the enhancement of drug activity and selective transfer or the reduction of side effects has been achieved by means of inclusion complex formation. Although the various CyDs described here have many advantages as novel drug carriers for development of advanced dosage forms, the toxicological issues together with their biological fates need to be investigated in detail.

Synthetic derivatives of N-acylated L-homoserine lactone (AHL), which is a key autoinducer for many quorum-sensing bacteria, interfere with quorum sensing in a range of dramatically different types of bacteria, according to chemist Helen Blackwell of the University of Wisconsin (UW)-Madison, and her colleagues. Because AHL and other similar, low-molecular-weight entities govern quorum sensing, “chemists can play an important role in trying to understand and elucidate signaling pathways by manipulating the signals themselves,” she says. Details appear in the January 3, 2011 ChemBioChem (DOI: 10.1002/cbic.201000551).

Two synthetic derivatives of the flavonol kaempferol were prepared in order to probe the biological mechanism of action of this natural product. Efficient synthetic routes to both a benzophenone-containing derivative and an amine-containing derivative are reported herein.

B-5354c is a new inhibitor of sphingosine kinase from a novel marine bacterium, SANK 71896. Kinetic study revealed that B-5354c inhibits sphingosine kinase with a Ki value of 12μM. The inhibition is noncompetitive with respect to sphingosine. The compound also inhibits sphingosine-1-phosphate formation in human platelets. Experiments using synthetic derivatives of B-5354c indicate that all the three functional groups, i.e., the long unsaturated aliphatic chain, 4-amino and 3-hydroxyl groups are necessary to inhibit sphingosine kinase.

Publisher Summary This chapter presents the evaluation of impurities in hormonal steroids and mainly their synthetic analogues is dealt with. Other non-hormonal synthetic derivatives (e.g. quaternary ammonium derivatives) and pharmaceutically less important groups of natural steroids such as sterols and bile acids are only briefly mentioned. These are very advantageous features from the points of view of their determination by UV spectrophotometry in various matrices and the detectability in the course of the TLC or HPLC analysis but are of little importance when the analytical task is the direct determination of impurities/degradation products in bulk drugs and their formulations. Several spectrophotometric methods based on (colour) reactions are also available but the importance of their application to the determination of impurities in steroid drugs has been surpassed by modem chromatographic methods.

Pharmacological applications of CDs are mainly based on an increase of the solubility of the active molecule entrapped. The development of pharmaceutical uses requires quantitative measurements of CD in biological material. We have developed different enzyme immunoassays (EIAs) specific for s-cyclodextrin (s-CD), di-2,6-O-methyl-s—cyclodextrin (di-Me-s-CD), tri-2,3,6-O-methyl-s-cyclodextrin (per-Me-s-CD) and γ—cyclodextrin (γ-CD). Specific s- and γ-CD EI As allowed us to perform qualitative and quantitative measurements of intact mono-6-amino-6-deoxy-s-CD (sCD-NH2) (after i.V. and oral administrations) and γ-cd (after i.V. administration) in rat biological fluids (plasma and urine). To our knowledge, this is the first pharmacokinetic study performed for these molecules using such specific immunological methods.

The 4-aminoquinoline chloroquine (1) can be considered to be one of the most important synthetic chemotherapeutic agents in history. Since its discovery, chloroquine has proved to be a highly effective, safe, and well-tolerated drug for the treatment and prophylaxis of malaria. However, the emergence of chloroquine-resistant strains of the malarial parasite has underlined the requirement for a synthetic alternative to chloroquine. This review describes structure-activity relationships for the 4-aminoquinolines, along with views on the mechanism of action and parasite resistance. A description of drug metabolism and toxicity also is included, with a brief description of potential approaches to the design of new synthetic derivatives.

Most medications with major potential for abuse and addiction belong to the sedative-hypnotic class. This encompasses benzodiazepines, barbiturates, and the opiates (including natural and synthetic derivations of opium) (Jaffe, 1990; Jaffe & Martin, 1990; Rall, 1990). This chapter is devoted to the sedative-hypnotic class, featuring benzodiazepines and including other sedative-hypnotic medications. In 1826 bromides were the first sedatives after alcohol to be marketed specifically for the sedative-hypnotic effects. Next, barbituric acid was introduced in 1903 followed by chloral hydrate (“Mickey Finn”) in 1932 and meprobamate in 1955. Morphine was discovered in 1806, followed by codeine in 1832, then development of the synthetic derivatives of opiates in the mid 1900s.

Controversy abounds regarding the use of anabolic growth-promoting agents, like estrogens, in food-producing animals and the human health risks associated with exposure to residues of these compounds in edible products from treated animals. The recent publicity on the increased risk of breast cancer in women undergoing postmenopausal estrogen replacement therapy and the reproductive abnormalities in alligators in Florida’s Lake Apopka caused by environmental contaminants has heightened consumers’ concerns over exposure to environmental estrogens that are present in the food supply as natural components or as environmental contaminants (Guillette et al, 1994; Hulka et al, 1994). Steroidal sex hormones and synthetic derivatives are used in the United States to enhance production in food-producing animals. More recently, steroidal and other hormonal agents have been used as reproductive aids for the synchronization of the ovarian cycle in certain food-producing species, thus assisting in herd management.

Symptoms of several human diseases are manifested as increased salivation (e.g., Parkinson’s disease) or decreased salivation (e.g., xerosis). Studies to find and to evaluate sialagogues, such as substance P and its synthetic derivatives, as well as to search for salivation inhibitors are necessary. Saliva excretion is greatly influenced by anesthetics. Wagner et al (1991) proposed a simple method to study saliva secretion in conscious rats and to evaluate sialagogues and sialagogue antagonists.

The dichloromethane extract of the tuberous roots of Viguiera aspillioides was tested in vitro against T. cruzi and then investigated in order to identify its active compounds, which were the known diterpenes (-)-ent-kaur-16-en-19-oic acid, (-)-trachyloban-19-oic acid, and (-)-kauran-16alpha-ol. Synthetic derivatives of the acidic compounds were obtained and tested; one of them, (-)-kaur-16-en-19-ol, was also active. Their IC50 are given.

This review discusses recent progress in the synthesis of inositol phosphates and their analogues. Most of the research published prior to 1992 has been extensively reviewed (Potter and Nahorski, 1992; Potter, 1990; Billington, 1989), probably most completely in the book by Billington (1993). Therefore, mainly findings published since then and some of the most important earlier results are covered by this chapter. A brief discussion of the biochemistry of intracellular inositol phosphates in respect to cell signaling is presented, followed by some of the most crucial stereochemical aspects of inositol phosphates. The synthesis of naturally occurring myo-inositol phosphates and their synthetic derivatives is covered. In particular, the efforts to find agonists and antagonists of the most prominent inositol phosphate, myo-inositol-l,4,5-trisphosphate [Ins(1,4,5)P3], are summarized, including some of their biochemical properties. Finally, some of the most widely used techniques for separation and identification of inositol phosphates are presented.

A simple and effective stereocontrolled synthesis of salinosporamide A (1) has been developed which follows the pathway outlined in the Figure. The process, the first total synthesis of salinosporamide A, is capable of providing the compound in substantial quantities for further biological studies. In addition to the method of Scheme I, the present invention also includes several novel synthetic intermediate compounds, several intermediate steps of the preferred synthetic process; and the uses of these compounds in the preparation of synthetic derivatives of the compound Salinosporamide A. Salinosporamide A is of special interest as a synthetic target because of its protein in vitro cytotoxic activity against many tumor cell lines (IC50 values of 10 nM or less).

Since the nineties anabolic steroids and steroid containing food supplements have been developed and marketed insistently in athletic world as legal nutritional supplements that can enhance performance of the athletes. Steroids are anabolic drugs that are actually the synthetic derivatives of testosterone. After the introduction of these products in the market, an abuse has been suspected in the sports community. Their usage and sale is widespread in the athletic environment, particularly in the events like football, body building, and weight lifting. Now their consistent use has been recognized as a serious health and ethical problem. Their misuse can cause psychological or emotional dependence.

Publisher Summary This chapter focuses on the structure or property relationships of polystannanes. Distannane, which can be considered a heavy-atom analog of ethane, is the simplest chemical structure that falls under the preceding definition for the class of compounds known as polystannanes. It has long been known that the electronic spectrum of hexaphenyldistannane exhibits a strong absorption maximum, which has been attributed to the presence of the Sn–Sn bond in this compound. Sulfur and selenium can similarly be inserted into the Sn–Sn bond, and while peralkyl distannanes are typically more reactive than peraryl ones, bulky substituents can retard these reactions by raising energy barriers for bimolecular processes. The use of sterically demanding substituents is, in fact, the basis for a strategy known as kinetic stabilization, which has been successfully employed for the synthesis of polystannane frameworks that would normally have highly reactive Sn–Sn bond. Propellanes are a class of nonclassical structures, since they possess bridgehead atoms having formally inverted tetrahedral geometries that force the four bonds from each of the bridgehead atoms to lie within the same hemisphere. Given this configuration, theoretical investigations have long sought to determine the stability and reactivity of these molecular frameworks prior to the availability of representative synthetic derivatives.

Vitamin A and its natural and synthetic derivatives have gained attention in the last five years as promising agents for the management of human cancer. The interest in their preventive role has been intense-although the number of completed trials have been few (see 24)-and this experience will not be repeated here. This current manuscript will summarize the progress that retinoids have demonstrated as potential therapeutic agents, since the first large report of their potential efficacy appeared-a phase II trial of 13-cis retinoic acid (13cRA) in advanced cancers (31).

In recent years, organocatalysis has enhanced its importance as a tool for the synthesis of enantiomerically enriched compounds. Among the candidates for organocatalysis, the construction of asymmetric quaternary carbons is regarded as a challenging problem in organic synthesis. In particular, 3,30-disubstituted oxindoles have one or more asymmetric quaternary carbon atoms and they represent a large family of bioactive compounds and synthetic derivatives that mimicry natural products. Therefore they are good targets for drug candidates and in the last two years many papers have appeared on organocatalytic methods for the synthesis of 3,30-disubstituted oxindoles. Moreover, in the last few years 2-substituted and 2,20-disubtituted 3-indolinones have also attracted the interest of chemists. This review aims to cover the literature on these topics from its origin to the end of 2011.

UV irradiation of cellular DNA leads to the formation of mutagenic pyrimidine derived dimer lesions. One of the stable end products of the lesion forming pathways are DNA Dewar lesions. Here we report that the TpC derived Dewar lesions are efficiently repaired by the repair enzyme (6-4) photolyase, while the TpT derived Dewar lesion is unrepairable. We provide experimental and theoretical data showing that the substituent of the Dewar substructure is mainly responsible for this behavior. Studies with synthetic derivatives of the Dewar lesions and theory reveal how the substitution pattern of the important Dewar lesions governs their reparability.

Hypocrellins are naturally occurring compounds with photosensitizing properties in biological systems. We have prepared synthetic derivatives of hypocrellin B, which have promise as photosensitizers in the clinical application of photodynamic therapy. The inherent fluorescence of four selected compounds has provided a means of determining their uptake and distribution in monolayer cultures of EMT6/Ed murine tumor cells, via fluorescence confocal microscopy.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Summary form only given. Studies of photoinduced electron transfer from a conducting polymer to C/sub 60/ and C/sub 61/ derivatives with 60 and 58 /spl pi/ electrons will be described. The molecules with 58 /spl pi/ electrons are the methanofullerenes; e.g., 1 and the molecules with 60 /spl pi/ electrons are the fulleroids (2). These molecules were made into composites with conjugated polymers such as MEH-PPV and the epi-cholestanoxy-PPV analogs. The photophysics of the various composites and the dramatic effect of electron count will be described. Other physicochernical phenomena related to fulleroid-methanofullerene isomerism will also be described.

IntroductionVarious synthetic derivatives of natural flavonoids are known to have neuroactive properties.ObjectivesIt has been reported that rutin (3, 3’, 4’, 5, 7-pentahydroxy flavone-3-rhamnoglucoside) has several pharmacological properties and it was found to be a neuroprotective agent.AimsTo investigate the effects of rutin, a flavonoid that is an important dietary constituent of foods and plant-based beverages, on memory retrieval in rats.MethodsWe assessed the effect of rutin on memory retrieval using a step- through passive avoidance task. Control (saline, 0.1 ml/100 g body weight) and rutin (5, 10, and 100 mg/kg) were administered intraperitoneally (i.p.) one week before the start of training. Three retention tests were performed to assess memory in rats.ResultsRutin (10 mg/kg) significantly increased the step-through latency of the passive avoidance response compared to the control in the three retention tests of the passive avoidance paradigm. These results indicate that rutin has a potential role in enhancing memory retrieval.ConclusionsIt is possible that rutin acts by several mechanisms, mediating a potential role in memory retrieval in rats. This result supports the potential beneficial effects of rutin as a dietary supplement on memory retrieval in a passive avoidance task.

The term “atypical opioid peptides” as used in this article requires definition. Opioid activity may be displayed by compounds with alkaloid or with peptide structure. Opioids with peptide structure may be of natural origin or they may be synthetic derivatives of the natural compounds. The natural opioid peptides may be subdivided again in “typical” and “atypical” opioid peptides; their synthetic derivatives thus may be subdivided in “typical” and “atypical” opioid peptide analogues.

The fluorinated quinolones are synthetic derivatives of nalidixic acid. They are well absorbed when administered orally and have an extended duration of action. They are of primary value in treating gonorrhea and complicated urinary tract infections in nonpregnant women.

This paper discusses the definition, pathogenesis, diagnosis and treatment of congenital anorchia. It concludes that preparations containing esters of testosterone are preferable to synthetic derivatives for long-term treatment as they are metabolized in the same way as endogenous testosterone. In addition, it appears that recommended doses for replacement therapy are lower than previously suggested. An ideal formulation of testosterone for use in androgen replacement therapy is not currently available.

Five new sesquiterpenoids, three monocyclofarnesane, and two cuparane derivatives, isolated from the liverwort Ricciocarpos natans (L.) Corda have been tested against Biomphalaria glabrata, one of the snail vectors of schistosomiasis (bilharzia). Molluscicidal activity is exhibited by four of the sesquiterpenoids with an LC100 of 11 ppm of the most toxic compound. Lunularic acid, a common growth inhibitor of liverworts, and five of its synthetic derivatives have also been tested, and two derivatives were found to be highly active.

Publisher Summary This chapter discusses the chemistry, biology, and pharmacology of peptides. Peptides are small proteins composed of fewer than 50 amino acids. Unlike most globular proteins, peptides frequently have modified amino (N) and carboxyl (C) termini, contain D-amino acids and multiple disulfide bridges, or exist in cyclic forms with linked N and C termini. These features not only contribute to the functional role of these compounds, but also confer stability in physiological environments, specifically by preventing proteolytic degradation. The number of naturally occurring peptides that have been identified and structurally characterized has grown substantially in the past decade as a result of improved protein purification and sequencing techniques and through the isolation of cDNAs encoding putative peptide like structures. The production of synthetic derivatives of these compounds, including competitive antagonists and potent agonists, the use of these agents in increasingly refined physiological studies, and the identification of their cellular receptors are gradually clarifying their functional role.

monly stated objectives. A less altruistic reason is that many of the floral species in such habitats remain unstudied and could yield new and important drugs to treat human diseases. Many of the drugs we use today are derived from plants or are their synthetic derivatives. While some plants are chosen at random for laboratory testing, others are selected because they are already being used in folk medicines. Most street markets in Brazil have stalls where it is possible to buy a wide variety of dried roots, leaves and other plant parts, each indicated for a specific ailment. Furthermore, herbal chemists selling 'natural' preparations, can be found on