Terpenoids From the Brown Alga Cystophora moniliformis

1988 ◽  
Vol 41 (1) ◽  
pp. 49 ◽  
Author(s):  
IA Vanaltena
Keyword(s):  
Brown Alga ◽  
Major Metabolite ◽  
New Compounds

The alga Cystophora moniliformis contains two new bisnorsesquiterpenes, (5E,9E)-5,6-epoxy-6,10,14-trimethylpentadeca-9,13-dien-2-one (3) and its cyclized derivative (4), and the (2E) and (2Z) isomers of geranylgeranal epoxide, (5) and (6), respectively. The structures of the new compounds were deduced by spectroscopic means. Geranylacetone (1) was the major metabolite present in the alga.

Four New Compounds from the Australian Brown Alga Cystophora brownii

1998 ◽  
Vol 51 (12) ◽  
pp. 1157 ◽  
Author(s):  
Baohong Bian ◽  
Ian A. van Altena
Keyword(s):  
Brown Alga ◽  
Two Dimensional ◽  
Chemical Methods ◽  
New Compounds

Two new steroids, (20S)-3β,20-dihydroxyergosta-5,24(28)-dien-16-one (7) and 3β-hydroxyergosta-5,24(28)-dien-16-one (9), and two new diastereoisomeric meroditerpenes, compounds (10) and (11), † have been isolated from the brown alga Cystophora brownii (Cystoseiraceae). Their structures were elucidated by one- and two-dimensional n.m.r. and other spectrometric and chemical methods.

Diterpenoid Hydroperoxides from the Far-Eastern Brown Alga Dictyota dichotoma

2009 ◽  
Vol 62 (9) ◽  
pp. 1185 ◽  
Author(s):  
Sophia A. Kolesnikova ◽  
Ekaterina G. Lyakhova ◽  
Anatoly I. Kalinovsky ◽  
Pavel S. Dmitrenok ◽  
Sergei A. Dyshlovoy ◽  
...  
Keyword(s):  
Cell Lines ◽  
Brown Alga ◽  
Human Cancer ◽  
Algal Species ◽  
Human Cancer Cell ◽  
Dictyota Dichotoma ◽  
Human Cancer Cell Lines ◽  
New Compounds ◽  
Far Eastern ◽  
First Time

Two new compounds, dictyohydroperoxide 1 and hydroperoxyacetoxycrenulide 2, (Scheme 1) containing hydroperoxyl groups rarely found in algal terpenoids were isolated from the Russian population of brown alga Dictyota dichotoma. The known compounds acetoxycrenulide 4 and squalene were also found in this algal species for the first time. Some of the isolated compounds showed moderate cytoxicity against human cancer cell lines.

scholarly journals Intraspecific variation of meroditerpenoids in the brown alga Stypopodium zonale guiding the isolation of new compounds

2015 ◽  
Vol 25 (6) ◽  
pp. 627-633 ◽  
Author(s):  
Angelica R. Soares ◽  
Heitor M. Duarte ◽  
Luzineide W. Tinnoco ◽  
Renato C. Pereira ◽  
Valéria L. Teixeira
Keyword(s):  
Intraspecific Variation ◽  
Brown Alga ◽  
Stypopodium Zonale ◽  
New Compounds

Crystal chemistry of high-Tc superconductors

1990 ◽  
Vol 48 (4) ◽  
pp. 1118-1119
Author(s):  
Maryvonne Hervieu
Keyword(s):  
Oxygen Deficiency ◽  
Large Family ◽  
Copper Oxides ◽  
High Tc Superconductors ◽  
High Tc ◽  
Single Mechanism ◽  
Square Planar ◽  
History Of ◽  
Bismuth Cuprates ◽  
New Compounds

Four years after the discovery of superconductivity at high temperature in the Ba-La-Cu-O system, more than thirty new compounds have been synthesized, which can be classified in six series of copper oxides: La2CuO4 - type oxides, bismuth cuprates, YBa2Cu3O7 family, thallium cuprates, lead cuprates and Nd2CuO4 - type oxides. Despite their quite different specific natures, close relationships allow their structures to be simply described through a single mechanism. The fifth first families can indeed be described as intergrowths of multiple oxygen deficient perovskite slabs with multiple rock salt-type slabs, according to the representation [ACuO3-x]m [AO]n.The n and m values are integer in the parent structures, n varying from 0 to 3 and m from 1 to 4; every member of this large family can thus be symbolized by [m,n]. The oxygen deficient character of the perovskite slabs involves the existence or the co-existence of several types of copper environment: octahedral, pyramidal and square planar.Both mechanisms, oxygen deficiency and intergrowth, are well known to give rise easily to nonstoichiometry phenomena. Numerous and various phenomena have actually been characterized in these cuprates, strongly depending on the thermal history of the samples.

Evaluation of New Compounds for Opioid Activity: Annual Report (1993)

1994 ◽  
Author(s):  
J. C. Woods ◽  
◽  
C. P. France ◽  
F. Medzihradsky ◽  
C. B. Smith ◽  
...  
Keyword(s):  
Annual Report ◽  
Opioid Activity ◽  
New Compounds

Effect of the marine brown alga Canistrocarpus cervicornis on promastigote forms of Leishmania (L.) amazonensis

Planta Medica ◽  
2009 ◽  
Vol 75 (09) ◽  
Author(s):  
AO Santos ◽  
EA Britta ◽  
T Ueda-Nakamura ◽  
BP Dias Filho ◽  
EM Bianco ◽  
...  
Keyword(s):  
Brown Alga ◽  
Canistrocarpus Cervicornis ◽  
Marine Brown Alga

A common mechanism links activities of butyrate in the colon

2017 ◽  
Author(s):  
Mohit S. Verma ◽  
Michael J. Fink ◽  
Gabriel L Salmon ◽  
Nadine Fornelos ◽  
Takahiro E. Ohara ◽  
...  
Keyword(s):  
Stem Cells ◽  
Histone Deacetylases ◽  
Biological Activities ◽  
Short Chain Fatty Acids ◽  
Common Mechanism ◽  
Epithelial Stem Cells ◽  
Degree Of Unsaturation ◽  
Structure Activity ◽  
Starting Point ◽  
New Compounds

Two biological activities of butyrate in the colon (suppression of proliferation of colonic epithelial stem cells and inflammation) correlate with inhibition of histone deacetylases. Cellular and biochemical studies of molecules similar in structure to butyrate, but different in molecular details (functional groups, chain-length, deuteration, oxidation level, fluorination, or degree of unsaturation) demonstrated that these activities were sensitive to molecular structure, and were compatible with the hypothesis that butyrate acts by binding to the Zn<sup>2+</sup> in the catalytic site of histone deacetylases. Structure-activity relationships drawn from a set of 36 compounds offer a starting point for the design of new compounds targeting the inhibition of histone deacetylases. The observation that butyrate was more potent than other short-chain fatty acids is compatible with the hypothesis that crypts evolved (at least in part), to separate stem cells at the base of crypts from butyrate produced by commensal bacteria.

Deep Reinforcement Learning for Multiparameter Optimization in de novo Drug Design

2019 ◽  
Author(s):  
Niclas Ståhl ◽  
Göran Falkman ◽  
Alexander Karlsson ◽  
Gunnar Mathiason ◽  
Jonas Boström
Keyword(s):  
Reinforcement Learning ◽  
Short Term Memory ◽  
De Novo ◽  
De Novo Drug Design ◽  
Generative Process ◽  
New Methods ◽  
Multiparameter Optimization ◽  
Long Short Term Memory ◽  
New Compounds

<p>In medicinal chemistry programs it is key to design and make compounds that are efficacious and safe. This is a long, complex and difficult multi-parameter optimization process, often including several properties with orthogonal trends. New methods for the automated design of compounds against profiles of multiple properties are thus of great value. Here we present a fragment-based reinforcement learning approach based on an actor-critic model, for the generation of novel molecules with optimal properties. The actor and the critic are both modelled with bidirectional long short-term memory (LSTM) networks. The AI method learns how to generate new compounds with desired properties by starting from an initial set of lead molecules and then improve these by replacing some of their fragments. A balanced binary tree based on the similarity of fragments is used in the generative process to bias the output towards structurally similar molecules. The method is demonstrated by a case study showing that 93% of the generated molecules are chemically valid, and a third satisfy the targeted objectives, while there were none in the initial set.</p>

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