Synthesis and biological activities of new 1α,25-dihydroxy-19-norvitamin D3 analogs with modifications in both the A-ring and the side chain

2006 ◽  
Vol 14 (12) ◽  
pp. 4277-4294 ◽  
Author(s):  
Masato Shimizu ◽  
Yukiko Miyamoto ◽  
Emi Kobayashi ◽  
Mika Shimazaki ◽  
Keiko Yamamoto ◽  
...  
Keyword(s):  
Biological Activities ◽  
Side Chain

Analogues of the cholecystokinin octapeptide modified in the central part of the molecule

1991 ◽  
Vol 56 (9) ◽  
pp. 1963-1970 ◽  
Author(s):  
Jan Hlaváček ◽  
Václav Čeřovský ◽  
Jana Pírková ◽  
Pavel Majer ◽  
Lenka Maletínská ◽  
...  
Keyword(s):  
Amino Acid ◽  
Biological Activities ◽  
Point Of View ◽  
Biologically Active ◽  
Side Chain ◽  
Amino Acid Residues ◽  
Cholecystokinin Octapeptide ◽  
Biological Tests ◽  
Biological Potency ◽  
Biologically Active Conformation

In a series of analogues of the cholecystokinin octapeptide (CCK-8) the amino acid residues were gradually modified by substituting Gly by Pro in position 4, Trp by His in position 5, Met by Cle in position 6, or the Gly residue was inserted between Tyr and Met in positions 2 and 3 of the peptide chain, and in the case of the cholecystokinin heptapeptide (CCK-7) the Met residues were substituted by Nle or Aib. These peptides were investigated from the point of view of their biological potency in the peripheral and central region. From the results of the biological tests it follows that the modifications carried out in these analogues and in their Nα-Boc derivatives mean a suppression of the investigated biological activities by 2-3 orders of magnitude (at a maximum dose of the tested substance of 2 . 10-2 mg per animal).This means that a disturbance of the assumed biologically active conformation of CCK-8, connected with a considerable decrease of the biological potency of the molecule, takes place not only after introduction of the side chain into its centre (substitution of Gly4), but also after the modification of the side chains of the amino acids or by extension of the backbone in further positions around this central amino acid.

scholarly journals Endo-fucoidan hydrolases from glycoside hydrolase family 107 (GH107) display structural and mechanistic similarities to α-l-fucosidases from GH29

2018 ◽  
Vol 293 (47) ◽  
pp. 18296-18308 ◽  
Author(s):  
Chelsea Vickers ◽  
Feng Liu ◽  
Kento Abe ◽  
Orly Salama-Alber ◽  
Meredith Jenkins ◽  
...  
Keyword(s):  
Glycoside Hydrolase ◽  
Biological Activities ◽  
Bacterial Species ◽  
Structural Data ◽  
Side Chain ◽  
Glycoside Hydrolase Family ◽  
X Ray Crystallography ◽  
Catalytic Mechanisms ◽  
Thickening Agents ◽  
Hydrolase Family

Fucoidans are chemically complex and highly heterogeneous sulfated marine fucans from brown macro algae. Possessing a variety of physicochemical and biological activities, fucoidans are used as gelling and thickening agents in the food industry and have anticoagulant, antiviral, antitumor, antibacterial, and immune activities. Although fucoidan-depolymerizing enzymes have been identified, the molecular basis of their activity on these chemically complex polysaccharides remains largely uninvestigated. In this study, we focused on three glycoside hydrolase family 107 (GH107) enzymes: MfFcnA and two newly identified members, P5AFcnA and P19DFcnA, from a bacterial species of the genus Psychromonas. Using carbohydrate-PAGE, we show that P5AFcnA and P19DFcnA are active on fucoidans that differ from those depolymerized by MfFcnA, revealing differential substrate specificity within the GH107 family. Using a combination of X-ray crystallography and NMR analyses, we further show that GH107 family enzymes share features of their structures and catalytic mechanisms with GH29 α-l-fucosidases. However, we found that GH107 enzymes have the distinction of utilizing a histidine side chain as the proposed acid/base catalyst in its retaining mechanism. Further interpretation of the structural data indicated that the active-site architectures within this family are highly variable, likely reflecting the specificity of GH107 enzymes for different fucoidan substructures. Together, these findings begin to illuminate the molecular details underpinning the biological processing of fucoidans.

Synthesis and antibacterial activity evaluation of C-5 side chain modified analogues of FYL-66, a potential agent against methicillin-resistant Staphylococcus aureus

MedChemComm ◽  
2015 ◽  
Vol 6 (6) ◽  
pp. 1156-1172 ◽  
Author(s):  
Xiaoyan Yang ◽  
Zicheng Li ◽  
Zhenling Wang ◽  
Zitai Sang ◽  
Haiyue Long ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
Animal Models ◽  
Antibacterial Agent ◽  
Methicillin Resistant Staphylococcus Aureus ◽  
Biological Activities ◽  
Side Chain ◽  
Methicillin Resistant ◽  
Activity Evaluation

Monofluoro- (39), difluoro- (40) and trifluoro- (41) substituted analogues showed different biological activities, and 40 is a potent antibacterial agent in animal models.

scholarly journals Discovery of Stealthin Derivatives and Implication of the Amidotransferase FlsN3 in the Biosynthesis of Nitrogen-Containing Fluostatins

Marine Drugs ◽  
2019 ◽  
Vol 17 (3) ◽  
pp. 150 ◽  
Author(s):  
Chunshuai Huang ◽  
Chunfang Yang ◽  
Zhuangjie Fang ◽  
Liping Zhang ◽  
Wenjun Zhang ◽  
...  
Keyword(s):  
Spectroscopic Data ◽  
Bioinformatics Analysis ◽  
Biological Activities ◽  
Side Chain ◽  
X Ray Diffraction ◽  
X Ray ◽  
Aromatic Polyketides ◽  
Plausible Mechanism ◽  
Encoding Gene

Diazobenzofluorene-containing atypical angucyclines exhibit promising biological activities. Here we report the inactivation of an amidotransferase-encoding gene flsN3 in Micromonospora rosaria SCSIO N160, a producer of fluostatins. Bioinformatics analysis indicated that FlsN3 was involved in the diazo formation. Chemical investigation of the flsN3-inactivation mutant resulted in the isolation of a variety of angucycline aromatic polyketides, including four racemic aminobenzo[b]fluorenes stealthins D–G (9–12) harboring a stealthin C-like core skeleton with an acetone or butanone-like side chain. Their structures were elucidated on the basis of nuclear magnetic resonance (NMR) spectroscopic data and X-ray diffraction analysis. A plausible mechanism for the formation of stealthins D–G (9–12) was proposed. These results suggested a functional role of FlsN3 in the formation/modification of N–N bond-containing fluostatins.

ChemInform Abstract: Synthesis and Biological Activities of New HMG-COA Synthase Inhibitors: 2-Oxetanones with a Side Chain Containing Biphenyl, Terphenyl, or Phenylpyridine.

ChemInform ◽  
2010 ◽  
Vol 25 (44) ◽  
pp. no-no
Author(s):  
H. HASHIZUME ◽  
H. ITO ◽  
N. KANAYA ◽  
H. NAGASHIMA ◽  
H. USUI ◽  
...  
Keyword(s):  
Biological Activities ◽  
Side Chain

scholarly journals Steroid Hydroxylation by Basidiomycete Peroxygenases: a Combined Experimental and Computational Study

2015 ◽  
Vol 81 (12) ◽  
pp. 4130-4142 ◽  
Author(s):  
Esteban D. Babot ◽  
José C. del Río ◽  
Marina Cañellas ◽  
Ferran Sancho ◽  
Fátima Lucas ◽  
...  
Keyword(s):  
Computational Study ◽  
Biological Activities ◽  
Side Chain ◽  
Enzymatic Reactions ◽  
Fungal Enzymes ◽  
Content Type ◽  
Protein Energy ◽  
Esterified Sterols ◽  
Ligand Diffusion ◽  
Protein Energy Landscape

ABSTRACTThe goal of this study is the selective oxyfunctionalization of steroids under mild and environmentally friendly conditions using fungal enzymes. With this purpose, peroxygenases from three basidiomycete species were tested for the hydroxylation of a variety of steroidal compounds, using H2O2as the only cosubstrate. Two of them are wild-type enzymes fromAgrocybe aegeritaandMarasmius rotula, and the third one is a recombinant enzyme fromCoprinopsis cinerea. The enzymatic reactions on free and esterified sterols, steroid hydrocarbons, and ketones were monitored by gas chromatography, and the products were identified by mass spectrometry. Hydroxylation at the side chain over the steroidal rings was preferred, with the 25-hydroxyderivatives predominating. Interestingly, antiviral and other biological activities of 25-hydroxycholesterol have been reported recently (M. Blanc et al., Immunity 38:106–118, 2013,http://dx.doi.org/10.1016/j.immuni.2012.11.004). However, hydroxylation in the ring moiety and terminal hydroxylation at the side chain also was observed in some steroids, the former favored by the absence of oxygenated groups at C-3 and by the presence of conjugated double bonds in the rings. To understand the yield and selectivity differences between the different steroids, a computational study was performed using Protein Energy Landscape Exploration (PELE) software for dynamic ligand diffusion. These simulations showed that the active-site geometry and hydrophobicity favors the entrance of the steroid side chain, while the entrance of the ring is energetically penalized. Also, a direct correlation between the conversion rate and the side chain entrance ratio could be established that explains the various reaction yields observed.

scholarly journals Synthesis of some side-chain homologues of 1.ALPHA.,25-dihydroxyvitamin D3 and investigation of their biological activities.

1986 ◽  
Vol 34 (11) ◽  
pp. 4508-4515 ◽  
Author(s):  
HIROSHI SAI ◽  
SUGURU TAKATSUTO ◽  
NOBUO IKEKAWA ◽  
YOKO TANAKA ◽  
HECTOR F. DELUCA
Keyword(s):  
Biological Activities ◽  
Side Chain ◽  
Dihydroxyvitamin D3

Design, synthesis and biological activities of new brassinosteroid analogues with a phenyl group in the side chain

2016 ◽  
Vol 14 (37) ◽  
pp. 8691-8701 ◽  
Author(s):  
M. Kvasnica ◽  
J. Oklestkova ◽  
V. Bazgier ◽  
L. Rárová ◽  
P. Korinkova ◽  
...  
Keyword(s):  
Molecular Docking ◽  
Biological Activities ◽  
Phenyl Group ◽  
Side Chain ◽  
Design Synthesis ◽  
Brassinosteroid Analogues

Synthesis of new brassinosteroid analogues based on molecular docking into the BRI1 receptor leads to novel compounds with bioactivity comparable to natural ones.

Aromatic Side Chain Analogs of Cationomycin and Their Biological Activities

1988 ◽  
Vol 52 (7) ◽  
pp. 1637-1641 ◽  
Author(s):  
Makoto Ubukata ◽  
Tomoko Akama ◽  
Kiyoshi Isono
Keyword(s):  
Biological Activities ◽  
Side Chain ◽  
Aromatic Side Chain
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