New basic mesoporous silica catalyst obtained by ammonia grafting.

NH3-treated mesoporous silica (FSM-16) contains SiNH2 sites which exhibit basic catalytic activity for Knoevenagel condensation; SiNH2 and SiOH pair sites formed at lower NH3-treatment temperatures exhibit higher turnover frequencies (TFs) in comparison with SiNH2 single sites.

Transfection of fluorescent probed antisense compounds: L-cysteine derivatives of nucleic acid bases.

Antisense with L-cysteine derivative (CAS) can recognize DNA and forms the complementary duplex with DNA. So the properties of CAS in vitro and in vivo were examined in this study. CAS was resistant to proteinase K and stabilized RNA against RNase HI. Moreover using fluorescent CAS, the localization was observed by fluorescence microscope and confocal microscope. As a result, CASs were accumulated inside the nucleus in NG108-15.

Study about the inhibition of L-cysteine derivatives of nucleic acid bases in protein production.

Isopoly (S-carboxymethyl-L-cysteine) derivatives of nucleic acids bases were prepared as antisense compounds. In past study, we investigated the properties of these compounds in vitro, and revealed that these compounds in vivo regulated the cell death presumably due to the inhibition of protein production. In this study, western and northern blots were carried out in order to reveal the mechanism of this inhibition for N-methyl-D-aspartate receptor in neuroblastoma x glioma hybrid NG108-15 cell line. In addition, we investigated the resistance of these compounds against cell extract and the metabolism. In conclusion, we proved that these compounds inhibited the protein production by antisense mechanism.

The behavior and effect of isopoly (S-carboxymethyl-L-cysteine) derivatives of nucleic acid bases.

Isopoly(S-carboxymethyl-L-cysteine) derivatives of nucleic acid bases were prepared as antisense compounds. These compounds in vitro have been found to form stable complex with oligo-DNA or RNA. This paper deals with effect of antisense compounds in vivo. The target in this paper is the sequence of the PSD-95 protein linked with NMDA receptor. Excess passing of calcium ions through the loss of the signal pathway without PSD-95 proteins caused by antisense compound. The cells detailing with L-cysteine derivatives showed the lowest percentage of 19.1%. The data were compared with that of phosphotioate antisense compound.

Structure and photodimerizations of 1-alkylthymines in single crystals.

1-Alkylthymine gave four kinds of crystals depending on the solvents used. Photodimerizations of 1-alkylthymine in single crystals were found to depend on the crystal structure. In inactive crystals, the terminal methyl group of alkyl chains approached to the double bond of thymine, and inhibited rotation of thymine bases during photodimerization.

Fluorescent probe and permeability to cells of isopoly (S-carboxymethyl-L-cysteine) derivative of nucleic acid bases.

Isopoly(S-carboxymethyl-L-cysteine) derivatives of nucleic acid bases were found to form stable complex with oligo-DNA in vitro. Fluorescent probed isopoly(S-carboxymethyl cysteine) derivatives of nucleic acid bases were prepared as antisense oligomers. The transfection of the oligomer into cells was carried out by HVJ-liposome method. Fluorescence was observed from the cells treated with HVJ-liposome including fluorescent probed oligomers.

Isopoly(S-carboxymethyl-L-cysteine) derivatives of nucleic acid bases: effects of D-cysteine derivatives on the interaction with DNA.

Isopoly(S-carboxymethyl-D-cysteine) derivatives of nucleic acid bases were prepared to study the effect of chirality on the complex formation with oligo-DNA. The D-cysteine unit in the L-cysteine oligomer caused decrease of Tm for the complex with DNA.

Specific interaction between 5'-aminonucleosides and borates and influence of borates on nucleoside conformations.

The unique conformation and orientational change of 5'-amino-5'-deoxyuridine in Kolthoff's buffer is discussed. From CD and NOE spectra, anomalous syn orientation of Urd-5'-NH2 might be caused by specific interaction between borates and Urd-5'-NH2, which promote the formation of hydrogen bonding between 2-carbonyl oxygen and hydrogen of 5'-amino group. This borates induced syn orientation of Urd-5'-NH2 could be applied to external stimulation control of target RNA/DNA hybridization.

Isopoly-L-ornithine derivative as nucleic acid model.

Isopoly-L-ornithine derivatives of thymine, and thymidine were found to hardly interact with poly A. Conformational studies of the oligomers with CD and NMR revealed that stable intramolecular hydrogen bonding was formed between the thymine base and the ornithine unit.

Synthesis and properties of oligo-omega-amino acids derivatives containing nucleosides.

Nucleic acid analogs, that consist of oligo-omega-amino acids as main chains were synthesized. At first, hydroxyl group of deoxy and ribonucleic acid was converted into amino or carboxylic acid group. Then, amino acid derivatives containing aminonucleoside or nucleoside-5'-carboxylic acid at alpha-position were synthesized. Amino acids used in this paper were L-glutamic acid, L-2-amino adipic acid (L-homo glutamic acid), L-ornithine, and L-lysine. These amino acid derivatives containing nucleoside were oligomerized by activated ester methods and Merrifield's solid phase synthesis. The properties of these analogs were studied and compared with oligo-alpha-amino acid derivatives containing nucleoside at omega-position.

Synthesis and properties of oligolysine and oligoglutamic acid derivatives containing nucleosides.

Nucleic acid analogs of L-lysine derivatives containing uridine and/or adenosine were synthesized. As dimer models, Lys(Urd)-Lys(Urd) and Lys(Urd)-Lys(Ado) were prepared by activated ester method. These dimers were found to form complex with poly(A), which was observed from hypochromicity of UV spectra. Furthermore, glutamic acid derivatives containing uridine and adenosine were also prepared. Oligomerization of glutamic acid derivatives were studied by Merrifield's solid phase synthesis.

Synthesis and interaction studies of watersoluble nucleic acid analogs containing serine as a spacer.

Watersoluble nucleic acid analogs containing L- or D-serine as a spacer were synthesized. Thymine was used as nucleic acid bases of these analogs. The base contents of these analogs were 93-94%. These analogs were found to form stable polymer complexes with Poly A or DNA by specific base-base interaction, which were observed from hypochromicity of UV spectra. In both cases, the maximum hypochromicity values of PEI-L-Ser-Thy were higher than that of PEI-D-Ser-Thy.

Immobilization of nucleoside on silica gel and specific separation of oligonucleotides.

Deoxyadenosine was immobilized on silica gel, in order to use as HPLC resins for selective separation of oligonucleotides. The longest retention time was observed for the complementary pd(T)4, and increased with decrease of temperature. This fact suggested that the main separation factor was the base pairing between complementary nucleic acid bases. These resins may be useful for separation of components of nucleic acids and polynucleotides as a specific separation system.

Synthesis and interaction studies of oligo and polyamino acids derivatives containing nucleosides.

Nucleic acid analogs of L-lysine derivatives containing uridine and/or adenosine were synthesized. As dimer models, Lys(Urd)-Lys(Urd) and Lys(Urd)-Lys(Ado) were prepared by activated ester method. These dimers were found to form complex with Poly A, which was observed from hypochromicity of UV spectra. Furthermore poly-L-lysine derivative containing uridine was also prepared. The maximum hypochromicity value of this polymer model with PolyA was higher than that of dimer models.

Watersoluble synthetic nucleic acid analogs--polyethyleneimine derivatives containing nucleic acid bases--conformation and interactionwith nucleic acids.

Water soluble polyethyleneimine derivatives containing nucleic acid bases were found to interact with polynucleotides, DNA, RNA. The conformational change by formation of complex was observed by CD spectra and was discussed with the hypochromicity in UV spectra. The rates of interactions between nucleic acid bases in polymers were slow as shown by UV spectra, but the conformational changes of the polynucleotides were fast as shown by CD spectra. In the case of the uracil derivative (PEI-Hse-Ura), high value of CD spectra [theta] 2.80 = -8.0 x 10(-4) for the complex with DNA might be caused by psi type conformation of DNA.

Nucleic acid analogs for high performance liquid chromatography.

HPLC resins containing nucleic acid base derivatives were successfully prepared. These resins were found to give excellent complementary separation of nucleic acid base derivatives, nucleosides, nucleotides, and oligonucleotides. These resins may be useful for separation of components of nucleic acids and polynucleotides as a specific separation system, while ion-exchange and reverse-phase systems are non-specific separation systems.

Synthesis of poly-L-glutamates containing 5-substituted uracil moieties.

The polymer reaction of cyclic derivatives of uracil and 5-bromouracil with polyacrylic and polymethacrylic acids, and poly-L-glutamic acid was studied in dimethylformamide solution. A similar reaction of cyclic derivatives of uridine with the polymeric acids was also made. Alkaline hydrolysis was further carried out on the polymers obtained.

Photoreaction of poly(amino acid)s containing thymine moieties as side groups.

The photodimerization reaction of thymine bases in poly-D,-L,and -DL-lysine and isopoly-L-lysine derivatives containing thymine bases was studied over a wide range of pH in aqueous buffered solution. It was found that the quantum yield of the intramolecular photodimerization of grafted thymine bases was affected by the conformation of the polymer in solution: alpha-helix or random coil. And the helical conformation was found to be favorable to cause the photodimerization of thymine bases. The photodimerization of the grafted thymine bases in poly-D, and -L-lysine derivatives caused to increase of the helix content of the poly-lysines, because the photodimer of thymine bases fixed alpha-helix of the polymer main chain.

Intramolecular interaction of thymine and adenine bases in synthetic oligo- and polynucleotide models.

Four types of oligomer systems, ranging from monomers to hexamers, of linear polyethyleneimine derivatives having pendant thymine or adenine bases were prepared. In order to evaluate the intramolecular interaction between the pendant nucleic acid bases, ultraviolet spectra at various pH regions and proton NMR spectra at various temperatures were measured. The results on UV hypochromicities and pKa values led to the clarification of such interaction between the bases: adenine bases can be prone to interact intramolecularly by stacking, while the interaction between thymine bases is not due to stacking, but due only to residual interaction which takes place between neighboring chromophores.

Synthesis and interactions of poly-L-lysines containing nucleic acid bases.

Poly-L-lysine derivatives containing nucleic acid bases were synthesized. Conformation of the obtained polymers was studied by CD and ORD. Formation of the polymer complex was studied and was related to the conformation of the polymers.