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Novel 2-chloro-1,4-dihydropyridine derivatives were synthesized by chlorination of 2-hydroxy-1,4-dihydropyridines with POCl3. The dihydropyridines chlorinated at position 2 exhibited more potent vasodilative and hypotensive activities than the dihydropyridines (nicardipine and nitrendipine) with a methyl group at position 2.
Several new class of phosphorus heterocyclic compounds containing exocyclic P-C link such as 6-(2'-chloroethyl)/(allyl)/(benzyl)-1,2,4,8,10,11-hexachloro-12H-dibenzo[d,g][1,3,2]dioxaphosphocin 6-oxides (5-7), 2-(2"-chloroethyl)/(allyl)-6-(1,1-dimethylethyl)-3-cyclohexyl-3,4-dihdro-2H-1,3,2-benzoxazaphosphorin 2-oxides (9, 10), 2-(2"-chloroethyl-2,3-dihydro-3-(4'-bromophenyl)-1H-naphth[1,2-e][1,3,2]-oxazaphosphorin 2-oxide (12), 2-(2"-chloroethyl)/(allyl)-2,3-dihydro-5-benzoyl-1H-1,3,2-benzodiazaphosphole 2-oxides (14, 15), 4-phenyl-2-(2"-chloroethyl)-1H-1,3,3a,5,6-pentaza-2-phosphapentalene 2-oxide (17) and 4-benzyl-2-(2"-chloroethyl)-1H-1,3,3a,5,6-pentaza-2-phospha-pentalene 2-oxide (19) were synthesized by reacting equimolar quantities of corresponding diol (4)/diamines (13, 16, 18), 2-cyclohexylaminomethyl-4-t-butylphenol (8) and 1-(4'-bromoanilinomethyl)-2-naphthol (11), with respective phosponyl dichlorides (1-3) in dry toluene/toluene-tetrahydro-furan/pyridine in the presence of triethylamine at various temperatures. Their structures were established by IR, (1)H-, (13)C- and (31)P-NMR spectral data. The mass spectral data were given for compounds 9, 12 and 15. The title compounds were screened for antibacterial activity against Staphylococcus aureus and Escherichia coli and antifungal activity on Aspergillus niger and Helminthosporium oryzae. Most of the compounds possess significant activity.
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A new route for synthesis of a 32P-labeled Edman reagent 2-(4-isothiocyanatophenoxy)-1,3,2-dioxaphosphinane 2-oxide (PEPITC) is reported. The carrier-free [32P]-PEPITC (specific radioactivity 3.3 X 10(17) Bq/mol) in theory allows the labeling and detection of a minimum amount of 0.1 femtomol of protein. The advantages of the new reagent, which has previously been used for protein sequencing, are demonstrated by gelelectrophoretical and immunological experiments. Its major role is seen in the quantitative monitoring of protein elution from preparative one- and two-dimensional gels. Proteins thus obtained are, after the usual desalting steps, ready for sequencing.
Phosphonated nucleosides represent a promising alternative in the improvement of the biological activity of nucleoside analogues in antiviral and anticancer chemotherapy. The basic concept, the chemistry, the different structural modifications and their effects on the antiviral potency will be discussed in this review.
The objective of this study was to synthesize a hybrid type filler composed of an organic component with inorganic component at the molecular level and to examine the properties of the filler. The composite resin was prepared by mixing synthesized filler with monomer and its physical properties were also examined. An organic-inorganic hybrid filler was synthesized by using 3-methacryloxypropyltrimethoxysilane (3-MPTS), methyltriethyoxysilane (MTES) and methanol silica sol. Firstly, poly3-methacryloxypropyltrimethoxysilane (poly3-MPTS) was synthesized by polymerization of 3-MPTS. A gelation product was obtained by graft-polymerization of poly3-MPTS with condensed organopolysiloxane after the hydrolysis of 3-MPTS, MTES and methanol silica sol. The gelation product was dried and ground to a filler. From the results of thermogravimetry-differential thermal analysis (TG-DTA), the organic-inorganic hybrid filler was found to be composed of 16.5 wt% organic component, 83.1 wt% inorganic component and 0.4 wt% residual water. A trial composite resin was prepared by mixing 55 wt% dimethacryloxyethyl 2,2,4-trimethylhexamethylene diurethane (UDMA), 15 wt% triethyleneglycol dimethacrylate (TEGDMA), 30 wt% 1-fluoro-1,3,3,5,5-penta (methacryloxyethyleneoxy) cyclotriphosphazene [P3N3(F)1 (EMA)5] as a base monomer and then 32.0 wt% of this monomer was mixed with 68.0 wt % of synthesized filler and a photo initiator, comphorquinone (CQ), was added. Compressive strength of the trial visible-light cured composite resin showed 397.0 MPa, and flexural strength and elastic modulus showed 142.5 MPa and 11.5 GPa, respectively. From the results, it was demonstrated that the present organic-inorganic hybrid filler at the molecular level can be used as a composite resin filler.
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Phosphorus-containing compounds of 18-d-old embryos from two broiler chicken lines, differing in body fat content, were measured using in vivo 31P nuclear magnetic resonance (NMR) spectroscopy. Subsequently, the same birds were slaughtered at 8 wk of age and the whole body was analyzed for body fat content. The birds of the fat line had lower (P = .002) embryonic adenosine triphosphate (ATP):phosphodiester (PDE) ratios, higher (P = .002) body fat content when adjusted to common BW, and higher (P = .047) dry matter content than the lean line. No differences (P > .05) were detected for BW between the two lines. Females of the two lines had lower (P = .002) ATP:PDE ratios, lower (P = .001) BW, higher (P = .003) adjusted fat contents, and higher (P = .003) dry matter content than the males. No interaction (P > .05) between sexes and lines was detected for any variables. Regression equations indicating a linear negative relationship (Ybody fat content = 369.05 - 407.27 XATP:PDE + .1295 XBW, R2 = .62 to .78; or Ybody fat % = 30.57 - 19.4 XATP:PDE, R2 = .49 to .71) between embryonic ATP:PDE ratios and body fat content were developed.
When reacted with mixtures of phosphorus pentoxide, aniline, and triethylamine hydrochloride, 5-acetamidoisoxazoles (2 and 3) gave isoxazolo[5,4-d]pyrimidines (4 and 7, respectively). The same reagent and cyclohexanone were used to prepare the isoxazoloquinoline 8.
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Pharmacokinetics of phosphamide-32P was studied in experiments on rats with sarcoma 45 and intact (tumourless) ones. Soon (15 min to 1 hour) after intraperitoneal injection of the compound the maximum amount of the isotope was definable in the liver, kidneys, spleen, suprarenals, in the tumour and the thymus. The content of the compound in the tumour ammounted to 0.2--0.4 per cent of the radioactivity introduced. Distribution of phosphemide-32P among organs and tissues of the rats with sarcoma 45 quatitatively differs from that in intact animals. During the first 24 hours 55--56 per cent of the radioactivity introduced is excreted together with urine.
Moderate activity of arginine kinase was found in Steinernema carpocapsae, an entomopathogenic nematode. In the forward reaction, 4.60 and 3.12 micromol ATP/min/mg protein was produced in infectious third-stage juveniles (J3s) and adult nematodes, respectively. For the reverse reaction, 3.20 and 2.27 micromol phosphoarginine/min/mg protein was produced by J3s and adults, respectively. The K(m)s for phosphoarginine and ADP were 0.73 and 0.42 mM, respectively, in the forward reaction, whereas in the reverse reaction, the K(m)s were 0.37 and 2.35 mM for arginine and ATP, respectively, for the enzyme from J3s. The pH optimum for the forward reaction was 7.2 and 7.3 in J3s and adults, respectively. The pH optimum was elevated for the reverse reaction, 7.8 and 7.9-8.5 in J3s and adults, respectively. In the J3s, the in vitro optima for arginine kinase activity was correlated with the in vivo tissue pH in hypoxic (6.9) and aerobic (7.5) J3s estimated by in vivo flow 31P-NMR.
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Intrinsic GTPase activity of GTP-binding proteins plays the vital role in regulating the downstream activation pathway. We examined the GTP and ATP hydrolyzing (NTPase) abilities of various bacterial and human GTP-binding proteins under different metabolic conditions. Two metabolic components, acetate and 3-phosphoglyceric acid (3-PG), have shown significant stimulatory action on NTPase activity of G-protein preparations. Acetyl phosphate and 2,3-bisphosphoglyceric acid (2,3-BPG) blocked these stimulations. From gel filtration analyses, we have determined two fractions containing metabolite-inducible NTPase activities which are independent of GTP-binding protein enzymatic actions. Therefore, one should be cautious when NTPase activity is examined in a buffer containing acetate often used for NTPase assay.
The 30 S ribosomal precursor RNA has been prepared from Escherichia coli AB301/105 (RNase III-) labeled with 32-PO4 in the presence of chloramphenicol. Direct nucleotide sequence studies yield the following information. 1. The major 5'-terminal sequence in our precursor preparations is pppA-C-U-G-. 2. Treatment of the precursor RNA with purified ribonuclease III in vitro releases species sedimenting near 23 S and 17 S, neither of which retain the pppA- end, plus a collection of small fragments with chain lengths of less than 400 nucleotides. 3. The RNase III product sedimenting near 17 S (16 SIII) appears identical with the 17 S RNA typically isolated from pulse-labeled or chloramphenicol-treated cells or from several mutants deficient in ribosome assembly: fingerprint analysis reveals the presence of the same additional RNase T1 oligonucleotides and the 5' terminus (pU-G-) previously described for 17 S RNA. A 3'-terminal T1 oligonucleotide (which was not previously identifiable in the case of the 17 S precursor) has been isolated from 16 S III and its sequence determined: C-U-C-A-C-A-C-A. 4. 5 S rRNA sequences are contained in an RNase III-released fragment of approximately 300 nucleotides. This molecule lacks the 5' terminus of the mature 5 S RNA. The implications of these findings with respect to the control of ribosomal RNA synthesis, the pathways of rRNA processing in vivo, and the specificity of RNase III cleavage of natural substrates are discussed.
White lupin (Lupinus albus) grown under P deficiency displays a suite of highly coordinated adaptive responses. Included among these is secretion of copious amounts of acid phosphatase (APase). Although numerous reports document that plants secrete APases in response to P deficiency, little is known of the biochemical and molecular events involved in this process. Here we characterize the secreted APase protein, cDNA, and gene from white lupin. The secreted APase enzyme is a glycoprotein with broad substrate specificity. It is synthesized as a preprotein with a deduced M(r) of 52,000 containing a 31-amino acid presequence. Analysis of the presequence predicts that the protein is targeted to outside the cell. The processed protein has a predicted M(r) of 49,000 but migrates as a protein with M(r) of 70,000 on sodium dodecyl sulfate gels. This is likely due to glycosylation. Enhanced expression is fairly specific to proteoid roots of P-stressed plants and involves enhanced synthesis of both enzyme protein and mRNA. Secreted APase appears to be encoded by a single gene containing seven exons interrupted by six introns. The 5'-upstream putative promoter of the white lupin-secreted APase contains a 50-base pair region having 72% identity to an Arabidopsis APase promoter that is responsive to P deficiency. The white lupin-secreted APase promoter and targeting sequence may be useful tools for genetically engineering important proteins from plant roots.