Novel Cytotoxic 4-Phenylfuranocoumarins from Calophyllum dispar

Eight new 4-phenylfuranocoumarins (1−8) have been isolated from the stem bark and the fruits of Calophyllum dispar, together with three known coumarins. The structures of 1−8 were established by means of spectroscopic analysis, including extensive 2D NMR studies. Some of these furanocoumarins exhibited significant cytotoxic activity against KB cells

Исследование особенностей динамики и растворения паромагниевых пузырей, всплывающих в расплаве чугуна

Разработана расчетная модель движения и физико-химического взаимодействия газомагниевых пузырей с расплавом чугуна. Проведенные расчеты показали, что в реальных условиях рафинирования чугуна при содержании серы в расплаве вплоть до 0,040%, начальном радиусе пузыря вплоть до 6,5 мм и глубине расплава 2,5 м и более происходит полное усвоение паров магния чугуном

Diverse Roles and Interactions of the SWI/SNF Chromatin Remodeling Complex Revealed Using Global Approaches

A systems understanding of nuclear organization and events is critical for determining how cells divide, differentiate, and respond to stimuli and for identifying the causes of diseases. Chromatin remodeling complexes such as SWI/SNF have been implicated in a wide variety of cellular processes including gene expression, nuclear organization, centromere function, and chromosomal stability, and mutations in SWI/SNF components have been linked to several types of cancer. To better understand the biological processes in which chromatin remodeling proteins participate, we globally mapped binding regions for several components of the SWI/SNF complex throughout the human genome using ChIP-Seq. SWI/SNF components were found to lie near regulatory elements integral to transcription (e.g. 5′ ends, RNA Polymerases II and III, and enhancers) as well as regions critical for chromosome organization (e.g. CTCF, lamins, and DNA replication origins). Interestingly we also find that certain configurations of SWI/SNF subunits are associated with transcripts that have higher levels of expression, whereas other configurations of SWI/SNF factors are associated with transcripts that have lower levels of expression. To further elucidate the association of SWI/SNF subunits with each other as well as with other nuclear proteins, we also analyzed SWI/SNF immunoprecipitated complexes by mass spectrometry. Individual SWI/SNF factors are associated with their own family members, as well as with cellular constituents such as nuclear matrix proteins, key transcription factors, and centromere components, implying a ubiquitous role in gene regulation and nuclear function. We find an overrepresentation of both SWI/SNF-associated regions and proteins in cell cycle and chromosome organization. Taken together the results from our ChIP and immunoprecipitation experiments suggest that SWI/SNF facilitates gene regulation and genome function more broadly and through a greater diversity of interactions than previously appreciated

Two new 3-methoxy-4-quinolone alkaloids from the bark of Sarcomelicope megistophylla

Two new alkaloids, megistonine I (1) and megistonine II (2), were isolated from the bark of Sarcomelicope megistophylla. Their structures, which are derived from the 3-methoxy-4-quinolone basic skeleton, were elucidated on the basis of MS and extensive NMR studies

The structure of sarcomejine: An application of long-range 1H-15N correlation at natural abundance

A new 4(1H)-quinolinone alkaloid, sarcomejine (1), has been isolated from the bark of Sarcomelicope megistophylla. Its structure has been elucidated on the basis of MS and NMR data and especially with a long-range 1H-15N correlation NMR spectrum at natural abundance

Megistolactone, a new alkaloid from Sarcomelicope megistophylla

A new quinolone alkaloid, megistolactone (1) was isolated from the bark of Sarcomelicope megistophylla. Its structure has been elucidated on the basis of MS and NMR data. From a biogenetic point of view, this compound should be considered as an oxidation product of 1,2,3,4-tetra-O-subsituted acridone alkaloids, which are also present in the bark

Troisième symposium sur les substances naturelles d'intérêt biologique de la région Pacifique-Asie : actes

Un nouvel alcaloïde de type oxindole, l'horsfiline 1, a été isolé de #Horsfieldia superba$ avec la 6-methoxy-2-methyl-1, 2, 3, 4-tetrahydro-"bêta"-carboline 2 et la 5-methoxy-N,N-dimethyltryptamine déjà décrites. La structure de 1 a été déterminée par une analyse spectrale et confirmée par sa synthèse à partir de 2. (Résumé d'auteur