7 research outputs found
The synthesis and in vitro activity of some Delta(7,9(11))-lanostadienes
The synthesis of Delta(7,9(11))-lanostadiene derivatives functionalized at C(32) starting from 3 beta-acetoxy-7 alpha,32-epoxylanostan-11-one has been presented. The Delta(7,9(11)) moiety was efficiently introduced in three steps in 71% yield by the regioselective abstraction of allylic 8 beta hydrogen. The formyl group of the key intermediate, 3 beta-benzoyloxylanosta-7,9(11)-dien-32-al, has been stereoselectively alkylated into (32S) derivative, whereas its oxidation unexpectedly afforded 3 beta-benxoyloxy-7-oxolanost-8-ene-32,11 alpha-lactone and not the corresponding acid. Delta(7,9(11))-lanostadienes possessing HC(32)=O, C(32)=N, HC(32S)CH3OH, H2C(32)OH, as well as some 11-keto lanostenes, were tested in vitro against several purified cholesterogenic enzymes showing moderate activity, with most the active aldehyde 16 having IC50 = 86 mu M. (C) 1997 by Elsevier Science, Inc
Synthesis and antiproliferative activity of A-ring aromatised and conduritol-like steroidal compounds
A simple approach to aromatization of steroidal quinols and epoxyquinols using a catalytic amount of TMSOTf is reported. Beside acetylation of the angular OH, the acid-catalyzed (TfOH) dienone-phenol rearrangement occurred affording "para" products, or in the case of blocked position 4, the acetoxy group 1,2-migration leads to the formation of "meta" products. Using epoxyquinol derivative as a substrate, the acetoxy group elimination was observed, followed by acid-catalyzed epoxy-ring opening and subsequent double bond migration, giving as a final product Delta(9,11) A-ring aromatized compounds. Synthesis of conduritol-like compounds and structure confirmation by X-ray crystallography of the precursor of steroidal conduritol is also described. In addition, the results of extensive antiproliferative screening against a panel of 60 cancer cell lines are presented. (c) 2005 Elsevier Inc. All rights reserved
Mixed steroidal 1,2,4,5-tetraoxanes: Antimalarial and antimycobacterial activity
Mixed 1,2,4,5-tetraoxanes possessing simple spirocycloalkane and spirocholic acid-derived substituents were prepared and shown to have significantly higher in vitro antimalarial activity than bis-substituted tetraoxanes. Out of 41 synthesized tetraoxanes, 12 were in vitro more potent against Plasmodium falciparum chloroquine-resistant W2 clone than artemisinin, and the most potent one was 2.4 times as active as arteether. In addition, 9 compounds exhibit higher activity than chloroquine against P. falciparum chloroquine-susceptible D6 clone. Cytotoxicity was assessed for most active compounds against the Vero cell line, showing a cytotoxicity/antimalarial potency ratio of 1/(1400-9500). For the first time, tetraoxanes were screened against Mycobacterium tuberculosis with MICs as low as 4.73 muM against H37Rv strain. Mixed tetraoxanes were synthesized in a simple procedure from cholic acid methyl esters by direct coupling of steroidal gem-dihydroperoxide to simple ketones and further transformed into corresponding acids and amides
Quinolines and Quinolones as Antibacterial, Antifungal, Antivirulence, Antiviral and Anti-parasitic Agents
Infective diseases have become health threat of
a global proportion due to appearance and
spread of microorganisms resistant to majority
of therapeutics currently used for their treatment.
Therefore, there is a constant need for
development of new antimicrobial agents, as
well as novel therapeutic strategies.
Quinolines and quinolones, isolated from
plants, animals, and microorganisms, have
demonstrated numerous biological activities
such as antimicrobial, insecticidal, antiinflammatory,
antiplatelet, and antitumor. For
more than two centuries quinoline/quinolone
moiety has been used as a scaffold for drug
development and even today it represents an
inexhaustible inspiration for design and development
of novel semi-synthetic or synthetic
agents exhibiting broad spectrum of
bioactivities. The structural diversity of
synthetized compounds provides high and
selective activity attained through different
mechanisms of action, as well as low toxicity
on human cells. This review describes quinoline
and quinolone derivatives with
antibacterial, antifungal, anti-virulent,
antiviral, and anti-parasitic activities with the
focus on the last 10 years literature
Basic Chemistry of Botulinum Neurotoxins Relevant to Vaccines, Diagnostics, and Countermeasures
Adaptation of the Wound Healing Questionnaire universal-reporter outcome measure for use in global surgery trials (TALON-1 study): mixed-methods study and Rasch analysis
BackgroundThe Bluebelle Wound Healing Questionnaire (WHQ) is a universal-reporter outcome measure developed in the UK for remote detection of surgical-site infection after abdominal surgery. This study aimed to explore cross-cultural equivalence, acceptability, and content validity of the WHQ for use across low- and middle-income countries, and to make recommendations for its adaptation.MethodsThis was a mixed-methods study within a trial (SWAT) embedded in an international randomized trial, conducted according to best practice guidelines, and co-produced with community and patient partners (TALON-1). Structured interviews and focus groups were used to gather data regarding cross-cultural, cross-contextual equivalence of the individual items and scale, and conduct a translatability assessment. Translation was completed into five languages in accordance with Mapi recommendations. Next, data from a prospective cohort (SWAT) were interpreted using Rasch analysis to explore scaling and measurement properties of the WHQ. Finally, qualitative and quantitative data were triangulated using a modified, exploratory, instrumental design model.ResultsIn the qualitative phase, 10 structured interviews and six focus groups took place with a total of 47 investigators across six countries. Themes related to comprehension, response mapping, retrieval, and judgement were identified with rich cross-cultural insights. In the quantitative phase, an exploratory Rasch model was fitted to data from 537 patients (369 excluding extremes). Owing to the number of extreme (floor) values, the overall level of power was low. The single WHQ scale satisfied tests of unidimensionality, indicating validity of the ordinal total WHQ score. There was significant overall model misfit of five items (5, 9, 14, 15, 16) and local dependency in 11 item pairs. The person separation index was estimated as 0.48 suggesting weak discrimination between classes, whereas Cronbach's α was high at 0.86. Triangulation of qualitative data with the Rasch analysis supported recommendations for cross-cultural adaptation of the WHQ items 1 (redness), 3 (clear fluid), 7 (deep wound opening), 10 (pain), 11 (fever), 15 (antibiotics), 16 (debridement), 18 (drainage), and 19 (reoperation). Changes to three item response categories (1, not at all; 2, a little; 3, a lot) were adopted for symptom items 1 to 10, and two categories (0, no; 1, yes) for item 11 (fever).ConclusionThis study made recommendations for cross-cultural adaptation of the WHQ for use in global surgical research and practice, using co-produced mixed-methods data from three continents. Translations are now available for implementation into remote wound assessment pathways