DOCSLIB.ORG

Diethyl Pyrocarbonate

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Diethyl Pyrocarbonate Proc. Nati. Acad. Sci. USA Vol. 82, pp. 8009-8013, December 1985 Biochemistry Diethyl pyrocarbonate: A chemical probe for secondary structure in negatively supercoiled DNA (chemical modification/alternating purines and pyrimidines/pBR322/Z-DNA) WINSHIP HERR Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724 Communicated by J. D. Watson, August 9, 1985 ABSTRACT Purine residues located within regions of ity, which can change with the linking number of the DNA, DNA that have the potential to form left-handed Z-helical and (ii) binding ofantibodies directed against the Z-form. The structures are modified preferentially by diethyl pyrocarbon- first method detects the loss of supercoils and, therefore, ate; this hyperreactivity is dependent on the degree of negative decreasing linking number caused by the transition from a superhelicity of the circular DNA molecules. As negative right-handed B-helix to the left-handed Z-form. With the superhelical density increases, guanosines in a 32-base-pair second method, anti-Z-DNA antibodies are bound to nega- alternating G-C sequence and adenosines (but not guanosines) tively supercoiled molecules, and binding sites are identified in a 64-base-pair alternating A-C/G-T sequence become 5- to either by electron microscopy or by the retention ofantibody- 10-fold more reactive to diethyl pyrocarbonate. The negative bound DNAs to nitrocellulose filters (7). An advantage ofthe superhelical densities at which enhanced reactivity occurs are electrophoretic analyses is that formation of Z-DNA cannot similar to those reported for the point at which left-handed be affected by interactions with antibodies. Alternatively, the helices form within plasmids carrying these DNA sequences. antibody studies have the advantages that sites of Z-DNA Probing of negatively supercoiled pBR322 with diethyl formation can be identified at higher negative superhelical pyrocarbonate reveals a hyperreactive region 31 base pairs in densities and the Z-DNA sites can be more readily mapped. length of which only 9 base pairs are a perfect alternating Neither ofthe methods, however, maps Z-DNA formation at purine and pyrimidine sequence; the reactivity of purines the nucleotide level. within this sequence indicates that purines in the anti confor- A method that does identify structure at the nucleotide mation, or guanosines in the syn conformation with neighbor- level in both DNA and RNA is chemical modification ing 3' thymidines, are not hyperreactive in the Z-DNA form. followed by strand scission at the modified sites (11, 12). This strategy relies on conformation-dependent reactivity ofbases DNA is a flexible molecule that can exist in a variety of to particular reagents. Diethyl pyrocarbonate, which conformations. One of the parameters influencing the equi- carbethoxylates purines at the N-7 atom (13, 14), is one such librium between these conformations is the stress created by reagent. In RNA, purines in double-stranded but not single- negative supercoils; increasing the negative supercoil density stranded regions are refractory to diethyl pyrocarbonate within closed circular DNA molecules has been shown to modification (12). In double-stranded DNA, however, stabilize the formation of single-stranded DNA, cruciform purines are accessible to this reagent (15). One interpretation structures, and the double-stranded Z-DNA form (1). Of of these results is that diethyl pyrocarbonate is less reactive these structures, Z-DNA is the best characterized, because of to purines in an RNA A-helix than to purines in a DNA the molecular detail afforded by high-resolution x-ray dif- B-helix. Such a possible conformational sensitivity suggested fraction studies (reviewed in ref. 2). that diethyl pyrocarbonate might serve to distinguish differ- Z-DNA is a left-handed double helix with a dinucleotide ent helical structures in DNA, in particular the B- and repeating unit. In the dinucleotide repeat, the bases along Z-forms. I therefore compared the relative diethyl pyro- each strand alternate between the syn and anti conforma- carbonate reactivity of purines within three sequences fa- tions; these two conformations are differentiated by a 180° vored for Z-DNA formation under negative superhelical rotation of the base around the glycosyl bond. Both stress: (i) an alternating G-C sequence, (ii) an alternating pyrimidines and purines are equally stable in the anti con- A-C/G-T sequence, and (ifi) a region ofpBR322 containing a formation (the structure found in the right-handed helix of stretch of nine alternating purines and pyrimidines (5-9, 16, B-DNA); in the syn conformation, however, pyrimidines are 17). I report here that, indeed, certain purines within all three less stable than purines (3, 4). The relative instability of of these sequences become hyperreactive to diethyl pyro- pyrimidines in the syn conformation offers an explanation for carbonate upon negative supercoiling. the fact that certain stretches of alternating purines and pyrimidines, e.g., repeating G-C or A-C/G-T stretches, are MATERIALS AND METHODS particularly favored for Z-DNA formation when under neg- ative superhelical stress (5-9). The crystal structure of a Plasmid DNAs. The three plasmid DNAs used, pLP32, nonalternating purine and pyrimidine oligonucleotide that is pAN064, and pBR322, were prepared by alkaline NaDodSO4 in the Z-form (10) implies that certain ofthese sequences can extraction (18) and CsCl equilibrium density gradient cen- also be induced to form Z-DNA under sufficient negative trifugation. DNAs with different linking numbers were pre- superhelical stress. pared by treatment with calf thymus topoisomerase I Two methods that have been used to identify Z-DNA in (Bethesda Research Laboratories) in the presence of closed circular molecules formed as a result of negative ethidium bromide, as described (6, 7), and the average linking supercoiling stress are (i) analysis of electrophoretic mobil- number of each DNA preparation was determined by the band counting method (6, 19). The superhelical density of was determined to DNAs The publication costs of this article were defrayed in part by page charge each sample by comparison treated payment. This article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. §1734 solely to indicate this fact. Abbreviation: bp, base pair(s). 8009 Downloaded by guest on September 26, 2021 8010 Biochemistry: Herr Proc. Natl. Acad. Sci. USA 82 (1985) with topoisomerase I under the conditions of diethyl pyrimidines near the unique Ava I site with only one pyrocarbonate modification. Linear DNAs were generated nucleotide out of alternation; this region has been identified by digestion with Pvu II for pLP32 and pANO64 and EcoRV as forming a negative-supercoil-dependent Z-DNA segment for pBR322. by antibody binding (7, 16, 17). Diethyl Pyrocarbonate Modification. Linear and super- Plasmid DNAs of different negative superhelical densities coiled plasmid DNAs were modified by diethyl pyrocarbon- were produced as described in Materials and Methods. The ate essentially as described (15). DNAs (1 Ag) were suspend- reactivities of specific bases to diethyl pyrocarbonate were ed in 200 t1 of 50 mM sodium cacodylate, pH 7.1/1 mM measured by modifying the DNAs with diethyl pyrocarbon- EDTA. The tubes were placed on ice and 3 1d of diethyl ate (15), isolating 3' or 5' singly end-labeled fragments pyrocarbonate was added to each sample. The samples were containing the regions of interest, cleaving the DNA at the incubated at 20'C for a total of 15 min. Because diethyl sites of modification with piperidine (11), and electrophores- pyrocarbonate is relatively insoluble in water, the samples ing the cleavage products through denaturing polyacrylamide were thoroughly mixed at the beginning and halfway through gels. the 15-min incubation. The reactions were terminated by the Reactivity of Guanosines Within an Alternating G-C Stretch addition of 50 Al of 1.5 M sodium acetate containing tRNA at to Diethyl Pyrocarbonate. The negative-supercoil-dependent 100 ,ug/ml, followed by two sequential rapid ethanol precip- diethyl pyrocarbonate reactivity of the 32-bp alternating G-C itations, as described (11, 20). The samples were then stretch ofpLP32 is shown in Fig. 1 (lanes 3-7). The reactivity suspended and stored in 50 dul of 10 mM Tris chloride, pH ofthe G-C stretch (identified by brackets in the figure) within 8.0/0.1 mM EDTA. Electrophoresis of the modified samples linear (lane 3) and closed circular pLP32 DNAs with average showed that little nicking ofthe closed circular molecules had superhelical densities of -0.014 (lane 4) and -0.029 (lane 5) occurred during the chemical modification. is similar to the reactivity of purines within the sequences End-Labeling, Strand Cleavage, and Gel Electrophoresis. flanking the G-C stretch. However, at higher superhelical After digestion with the appropriate restriction enzyme, densities [-0.045 (lane 6) and -0.062 (lane 7)], the reactivity modified DNAs were labeled at either the 5' end with of guanine residues within the G-C stretch increases dramat- polynucleotide kinase or the 3' end with the large fragment of ically as shown by the 5- to 10-fold increase in band intensity DNA polymerase I. End-labeled fragments were recleaved (compare lanes 5 and 6). This transition in diethyl pyro- with a second restriction enzyme and purified by electropho- carbonate reactivity correlates with formation of a left-hand- resis through 5% native polyacrylamide gels. Fragments were ed helix within the alternating G-C stretch (see Discussion). eluted by diffusion overnight at room temperature in 0.5 M To demonstrate that the observed diethyl pyrocarbonate ammonium acetate/0.05% NaDodSO4/1 mM EDTA with 10 hyperreactivity of purines was due to modification under the Mug of tRNA carrier. After ethanol precipitation, the strands defined reaction conditions, two identical samples of of the purified fragments were cleaved at the sites of diethyl supercoiled pLP32 were treated with diethyl pyrocarbonate, pyrocarbonate modification by treatment with 25 Al of 1 M but only one of the samples (Fig.
Load more

Recommended publications
  • Diethyl Pyrocarbonate at Ph6.5, When 0.58+0.1Residue Of
    Aiochem. J. (1974) 139, 797-800 797 Printed in Great Britain Histidine Residues and the Enzyme Activity of Pig Heart Supernatant Malate Dehydrogenase By J. JOHN HOLBROOK, A. LODOLA and NICHOLAS P. ILLSLEY Department ofBiochemistry, University ofBristol, Bristol BS8 1TD, U.K. (Received 25 February 1974) 1. Supernatant pig heart malate dehydrogenase is completely inhibited by reaction with diethyl pyrocarbonate at pH6.5, when 0.58+0.1 residue of ethoxycarbonylhistidine is formed per NADH-binding site. 2. Oxaloacetate and hydroxymalonate protect the en- zyme from inhibition in the absence of coenzyme. 3. Limited ethoxycarbonylation does not alter the binding of NADH to the enzyme but prevents the enzyme-NADH complex from interacting with hydroxymalonate in a ternary complex. Supematant malate dehydrogenase and lactate de- and the crystals were dissolved in 20mM-H3P04 hydrogenase have very similar tertiary structures adjusted to pH6.5 with 5M-NaOH and then filtered (Hill et al., 1972; Adams et al., 1972). Histidine-195 through a column of Sephadex G-50 equilibrated in plays a central role in the activity of lactate dehydro- the same buffer. If (NH4)2SO4 was not completely genase as the acceptor and donor of the proton in- removed it competed effectively for the diethyl pyro- volved in the reaction (Holbrook & Gutfreund, 1973). carbonate. This latter reagent was obtained from A proton is also a reactant for malate dehydrogenase, Sigma (London) Chemical Co., Kingston-on- and the work reported here is an attempt to discover Thames, U.K., and the batch used in these experi- if this enzyme also has a histidine residue with the ments was 2.6M when assayed as described by same function as histidine-195 of lactate dehydro- Holbrook & Ingram (1973).
    [Show full text]
  • Flammable Liquids and Solids Chemical Class Standard Operating Procedure
    1 Flammable Liquids and Solids Chemical Class Standard Operating Procedure Flammable Liquids and Solids H224 H225 H226 H227 H228 This SOP is not a substitute for hands-on training. Print a copy and insert into your laboratory SOP binder. Department: Chemistry Date SOP was written: Thursday, July 1, 2021 Date SOP was approved by PI/lab supervisor: Thursday, July 1, 2021 Name: F. Fischer Principal Investigator: Signature: ______________________________ Name: Matthew Rollings Internal Lab Safety Coordinator or Lab Manager: Lab Phone: 510.301.1058 Office Phone: 510.643.7205 Name: Felix Fischer Emergency Contact: Phone Number: 510.643.7205 Tan Hall 674, 675, 676, 679, 680, 683, 684 Location(s) covered by this SOP: Hildebrand Hall: D61, D32 1. Purpose This SOP covers the precautions and safe handling procedures for the use of Flammable Liquids and Solids. For a list of Flammable Liquids and Solids covered by this SOP and their use(s), see “List of Chemicals”. Procedures described in Section 12 apply to all materials covered in this SOP. A change to the “List of Chemicals” does not constitute a change in the SOP requiring review or retraining. If you have questions concerning the applicability of any recommendation or requirement listed in this procedure, contact the Principal Investigator/Laboratory Supervisor or the campus Chemical Hygiene Officer at [email protected]. Rev. Date: 2021-06-29 2 Flammable Liquids and Solids Chemical Class Standard Operating Procedure 2. Physical & Chemical Properties/Definition of Chemical Group Flammable liquid means a liquid having a flash point1 of not more than 199.4 °F (93 °C).
    [Show full text]
  • The Irreversible Cleavage of Histidine Residues by Diethylpyrocarbonate (Ethoxyformic Anhydride)
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Elsevier - Publisher Connector Volume 72, number 1 FEBS LE’M-ERS December 1976 THE IRREVERSIBLE CLEAVAGE OF HISTIDINE RESIDUES BY DIETHYLPYROCARBONATE (ETHOXYFORMIC ANHYDRIDE) M. J. LOOSEMORE and R. F. PRATT Chemistry Department, Wesleyan University, Middletown, CT 06457, USA Received 4 October 1976 1 . Introduction 2. Materials and methods In aqueous solution at neutral or slightly acidic pH DEP was obtained from Aldrich Chemical Co. and values diethyl pyrocarbonate (ethoxyformic anhydride, used without further purification. The modification DEP) has been shown to modify histidine residues in reactions in 0.1 M phosphate buffer at pH 6.0 and proteins with considerable specificity [l-3] . For this 30°C of 0.2 mM solutions of imidazole, histidine, reason DEP has been widely used to test for the N-acetylhistidine and glycylhistidylglycine (all from presence of functional histidine residues at the active Sigma Chemical Co.) on addition of DEP to a final sites of enzymes; for example, phosphofructokinase concentration of l-5 mM (added as 5-20 ~1 of an [4], thermolysin [5,6], lactate dehydrogenase [7], acetonitrile or ethanol solution to 3 ml of imidazole pyruvate kinase [8] , and liver alcohol dehydrogenase solution) were followed spectrally with a Cary 14 [9]. The reagent is convenient since it reacts with spectrophotometer. The products of DEP-modified histidine to give an ultraviolet spectral change centered imidazole were isolated by chloroform extraction of a at 240 nm [2,3] from the intensity of which the number 12 h room-temperature reaction mixture obtained by of modified histidine residues can be estimated and the stirring in 20 ml of an acetonitrile solution of DEP to modification reaction can be reversed by cleavage of 1 .O litre of an aqueous solution of 2 mM imidazole in the product, Ncarbethoxyhistidine, with suitable 0.1 M phosphate buffer, pH 6.0 (final DEP concentra- nucleophiles such as hydroxylamine.
    [Show full text]
  • EAFUS: a Food Additive Database
    U. S. Food and Drug Administration Center for Food Safety and Applied Nutrition Office of Premarket Approval EAFUS: A Food Additive Database This is an informational database maintained by the U.S. Food and Drug Administration (FDA) Center for Food Safety and Applied Nutrition (CFSAN) under an ongoing program known as the Priority-based Assessment of Food Additives (PAFA). It contains administrative, chemical and toxicological information on over 2000 substances directly added to food, including substances regulated by the U.S. Food and Drug Administration (FDA) as direct, "secondary" direct, and color additives, and Generally Recognized As Safe (GRAS) and prior-sanctioned substances. In addition, the database contains only administrative and chemical information on less than 1000 such substances. The more than 3000 total substances together comprise an inventory often referred to as "Everything" Added to Food in the United States (EAFUS). This list of substances contains ingredients added directly to food that FDA has either approved as food additives or listed or affirmed as GRAS. Nevertheless, it contains only a partial list of all food ingredients that may in fact be lawfully added to food, because under federal law some ingredients may be added to food under a GRAS determination made independently from the FDA. The list contains many, but not all, of the substances subject to independent GRAS determinations. The list below is an alphabetical inventory representing only five of 196 fields in FDA/CFSAN's PAFA database. To obtain the entire database, including abstractions of over 7,000 toxicology studies performed on substances added to food as well as a search engine to locate desired information, order Food Additives: Toxicology, Regulation, and Properties, available in CD-ROM format from CRC Press.
    [Show full text]
  • Active-Site Characterization of Si Nuclease II
    Biochem. J. (1992) 288, 571-575 (Printed in Great Britain) 571 Active-site characterization of Si nuclease II Involvement of histidine in catalysis Sadanand GITE,* Gurucharan REDDY*t and Vepatu SHANKAR*t *Division of Biochemical Sciences, National Chemical Laboratory, Pune 411 008, India Modification of the histidine residues of purified SI nuclease resulted in loss of its single-stranded (ss)DNAase, RNAase and phosphomonoesterase activities. Kinetics of inactivation indicated the involvement of a single histidine residue in the catalytic activity of the enzyme. Furthermore, histidine modification was accompanied by the concomitant loss of all the activities of the enzyme, indicating the presence of a common catalytic site responsible for the hydrolysis of ssDNA, RNA and 3'-AMP. Substrate protection was not observed against Methylene Blue- and diethyl pyrocarbonate (DEP)-mediated inactivation. The histidine (DEP)-modified enzyme could effectively bind 5'-AMP, a competitive inhibitor of S1 nuclease, whereas the lysine (2,4,6-trinitrobenzenesulphonicracid)-modified enzyme showed a significant decrease in its ability to bind 5'-AMP. The inability of the substrates to protect the enzyme against DEP-mediated inactivation, coupled with the ability of the modified enzyme to bind 5'-AMP effectively, suggests the involvement of histidine in catalysis. INTRODUCTION 10600 M-1 * cm-' for deoxyribonucleotide and ribonucleotide mix- tures respectively (Curtis et al., 1966). One unit of ssDNAase or Single-strand specific nuclease from Aspergillus oryzae (Sl RNAase activity is defined as the amount of enzyme required to nuclease, EC 3.1.30.1) is an analytically important enzyme, used liberate 1 of acid-soluble nucleotides per minute under the extensively for the characterization of nucleic-acid structure /tmol assay conditions.
    [Show full text]
  • DEPC-Treated Water Rev 12/20
    FOR RESEARCH ONLY! DEPC-Treated Water Rev 12/20 ALTERNATE NAMES: RNase- and DNase-free water, RNase-free water, Molecular Biology Grade water, DEPC Water, Sterile water CATALOG #: M1500-100 100 ml M1500-1000 1 L APPEARANCE: Clear, Colorless liquid FEATURES: Ready-to-use Solution For RNA experiments RNase and DNase Free Molecular Biology Grade FORMULATION: 0.1 % v/v Diethyl Pyrocarbonate (DEPC) in water DESCRIPTION: DEPC is a non-specific inhibitor of Ribonucleases (RNases). To reduce degradation of RNA in experiments, water is treated with DEPC. The concentration of DEPC is 0.1%. Ultra-pure molecular biology grade water is treated with DEPC followed by auto-claving. Autoclaving inactivates DEPC by causing hydrolysis of DEPC and release of by-products ethanol and carbon-dioxide. DEPC modifies enzymes containing -NH, -SH, or -OH groups in their active sites. DEPC particularly reacts with Cys, His, Lys, Ser and Tyr residues of proteins. DEPC has a half-life of approximately 30 min in water. DEPC-Treated Water (0.1%) can be used with buffers such as PBS and MOPS but cannot be used with the buffers Tris and HEPES. Tris and HEPES make DEPC unavailable to inactivate RNase. DEPC-treated water should not be added to aqueous solutions of ammonia as it will result in the formation of urethane, a possible carcinogen. qPCR, Real-Time RT-PCR, cDNA synthesis and RNase protection assays APPLICATIONS: STORAGE TEMPERATURE: Room Temperature. Avoid long exposure to UV light. HANDLING: Do not take internally. Wear gloves and mask when handling the product! Avoid contact by all modes of exposure.
    [Show full text]
  • Reaction of Diethyl Pyrocarbonate with Nucleic Acid Components, I
    Proceedings ofthe National Academy of Sciences Vol. 67, No. 1, pp. 93-98, September 1970 Reaction of Diethyl Pyrocarbonate with Nucleic Acid Components, I. Adenine* Nelson J. Leonard, Jerome J. McDonald, and M. E. Reichmann DEPARTMENTS OF CHEMISTRY AND CHEMICAL ENGINEERING AND BOTANY, UNIVERSITY OF ILLINOIS, URBANA 61801 Communicated June 30, 1970 Abstract. The use of diethyl pyrocarbonate as a nuclease inhibitor in the preparation of RNA of high molecular weight has prompted a study of the possible reactions of this compound with nucleic acid components under the conditions generally employed for providing inhibition. The first substrate investigated was adenine, which has been found to undergo ring opening with the formation of 5(4)-N-carbethoxyaminoimidazole-4(5)-N'-carbethoxycarbox- amidine (II). This product was converted efficiently to isoguanine by treatment with ammonia. The structure of II was established by spectroscopy. For comparisons of reactivity and of spectroscopic and chromatographic prop- erties with the adenine-diethyl pyrocarbonate product, the compounds 9-car- bethoxyadenine, 6-N-carbethoxyaminopurine (V), and 6-ethylaminopurine were made; compound V was made by employing the 1-ethoxyethyl protecting group in the synthetic sequence. Purine compounds can be converted to 9-(1-ethoxy- ethyl) derivatives simply by refluxing in acetal. The facile reaction of adenine with diethyl pyrocarbonate illustrates the im- portance of gaining information as to the fate of various nucleic acid components in the presence of diethyl pyrocarbonate. The successful preparation of high molecular weight, biologically active RNA depends on the rapid inactivation of nucleases in the early steps of the isolation. Conservation of biological activity upon prolonged storage also requires the total absence of nuclease activity in these preparations.
    [Show full text]
  • Flammable Liquids and Solids Chemical Class Standard Operating Procedure
    Flammable Liquids and Solids Chemical Class Standard Operating Procedure Flammable Liquids and Solids H224 H225 H226 H227 H228 Areas with blue text indicate that information must be provided or modified by researcher prior to the SOP approval. This SOP is not a substitute for hands-on training. Print a copy and insert into your laboratory SOP binder. Department: Chemistry Date SOP was written: Monday, October 24, 2016 Date SOP was approved by PI/lab supervisor: Name: R. Sarpong Principal Investigator: Signature: ______________________________ Name: Melissa Hardy/Justin Jurczyk Internal Lab Safety Coordinator or Lab Manager: Lab Phone: 406-696-1225/412-728-1952 Office Phone: 510-642-6312 Name: Melissa Hardy/Justin Jurczyk Emergency Contact: Lab Phone: 406-696-1225/412-728-1952 Latimer Hall Location(s) covered by this SOP: 831,832,834,836,837,838,839,842,844,847,849 1. Purpose This SOP covers the precautions and safe handling procedures for the use of Flammable Liquids and Solids. For a list of Flammable Liquids and Solids covered by this SOP and their use(s), see “List of Chemicals”. Procedures described in Section 12 apply to all materials covered in this SOP. If you have questions concerning the applicability of any recommendation or requirement listed in this procedure, contact the Principal Investigator/Laboratory Supervisor or the campus Chemical Hygiene Officer at [email protected]. Rev. Date: 09Sept2016 1 Flammable Liquids and Solids Chemical Class Standard Operating Procedure 2. Physical & Chemical Properties/Definition of Chemical Group Flammable liquid means a liquid having a flash point1 of not more than 199.4 °F (93 °C).
    [Show full text]
  • 1,2-Bis[(2R ,5R )-2,5-Diethylphospholano]Benzene
    TABELLA DI STIMA CONSUMO ANNUALE LOTTO 1B UNIPV REAGENTI CHIMICI QUANTITA' Unità di CAS Number PRODOTTO ANNUA Misura 136705-64-1 (−)-1,2-Bis[(2R ,5R )-2,5-diethylphospholano]benzene 0,350 g 83-88-5 (-)-RIBOFLAVIN 87,500 g 225937-10-0 (+)-CATECHIN HYDRATE 17,500 g 706-14-9 (+)-GAMMA-DECALACTONE, >=97% 350,000 g 75-56-9 (+/-)-PROPYLENE OXIDE 0,8750 l 480438-44-6 (1,3-DIOXAN-2-YLETHYL)MAGNESIUM BROMIDE 0,350 l 470480-32-1 (1S ,1S ′,2R ,2R ′)-1,1′-Di-tert -butyl-(2,2′)-diphospholane 0,350 g 919-30-2 (3-AMINOPROPYL)TRIETHOXYSILANE, >=98.0% 0,700 l 14867-28-8 (3-IODOPROPYL)TRIMETHOXYSILANE, >=95.0% 0,08750 l 4420-74-0 (3-MERCAPTOPROPYL)TRIMETHOXYSILANE, 95% 700,000 g 2712-78-9 (BIS(TRIFLUOROACETOXY)IODO)BENZENE, 97% 175,000 g 1833-51-8 (CHLOROMETHYL)DIMETHYLPHENYLSILANE, 98% 70,000 g 5293-84-5 (CHLOROMETHYL)TRIPHENYLPHOSPHONIUM 87,500 g 364732-88-7 (R )-(–)-4,12-Bis(diphenylphosphino)-[2.2]-paracyclophane 0,350 g (R )-(−)-5,5′-Bis[di(3,5-di-tert -butyl-4-methoxyphenyl)phosphino]-4,4′-bi-1,3- 566940-03-2 benzodioxole 0,350 g 5989-27-5 (R)-(+)-LIMONENE, 98% 0,350 l 138517-61-0 (R,R)-DACH-PHENYL TROST LIGAND, 95% 0,8750 g 5989-54-8 (S)-(-)-LIMONENE, >=95% 3500,000 g 29394-58-9 (S)-(+)-1-IODO-2-METHYLBUTANE 17,500 g (S)-2-(4′-Bromo-biphenyl-4-sulfonylamino)-3-methyl-butyric acid hydrate 0,01750 g 138517-65-4 (S,S)-ANDEN-PHENYL TROST LIGAND 0,350 g 1066-54-2 (TRIMETHYLSILYL)ACETYLENE, 98% 175,000 g 18107-18-1 (TRIMETHYLSILYL)DIAZOMETHANE, 2.0 M in diethyl ether 0,08750 l 436863-50-2 1,1''-BIS((2S,5S)-2,5-DIETHYLPHOSPHOLANO 0,350 g 530-62-1 1,1'-CARBONYLDIIMIDAZOLE,
    [Show full text]
  • Technical Report for the Substantial Modification Rule for 62-730, F.A.C
    Technical Report for the Substantial Modification Rule for 62-730, F.A.C. Prepared for the Hazardous Waste Regulation Section Florida Department of Environmental Protection By Kendra F. Goff, Ph. D. Stephen M. Roberts, Ph.D. Center for Environmental & Human Toxicology University of Florida Gainesville, Florida August 1, 2008 During an adverse event, such as a fire or explosion, hazardous materials from a storage or transfer facility may be released into the atmosphere. The potential human health impacts of such a release are assessed through air modeling coupled with chemical-specific inhalation criteria for short-term exposures. With this approach, distances from the facility over which differing levels of health effects from inhalation of airborne hazardous materials are expected can be predicted. Because the movement in air and toxic potency varies among chemicals, the potential impact area for a facility is dependent upon the chemicals present and their quantities. The impact area can be calculated for a facility under current and possible future conditions. This information can be used to determine whether proposed changes in storage conditions or the nature and quantities of chemicals handled would result in a substantial difference in the area of potential impact. The following sections provide technical guidance on how impact areas for facilities handling hazardous materials under Chapter 62-730, F.A.C. should be determined. Air modeling. Any model used for the purposes of demonstration must be capable of producing results in accordance with worst-case scenario provisions of Program 3 of the Accidental Release Prevention Program of s. 112(r)(7) of the Clean Air Act.
    [Show full text]
  • Activation of Carboxylic Acids by Pyrocarbonates
    This article was downloaded by: [University of Delaware] On: 11 June 2012, At: 08:03 Publisher: Taylor & Francis Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House, 37-41 Mortimer Street, London W1T 3JH, UK Organic Preparations and Procedures International: The New Journal for Organic Synthesis Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/uopp20 ACTIVATION OF CARBOXYLIC ACIDS BY PYROCARBONATES. SCOPE AND LIMITATIONS. A REVIEW V. F. Pozdnev a a Institute of Biomedical Chemistry, Russian Academy of Medical Sciences, Pogodinskaya st., 10, Moscow, 119832, RUSSIA Available online: 09 Feb 2009 To cite this article: V. F. Pozdnev (1998): ACTIVATION OF CARBOXYLIC ACIDS BY PYROCARBONATES. SCOPE AND LIMITATIONS. A REVIEW, Organic Preparations and Procedures International: The New Journal for Organic Synthesis, 30:6, 631-655 To link to this article: http://dx.doi.org/10.1080/00304949809355325 PLEASE SCROLL DOWN FOR ARTICLE Full terms and conditions of use: http://www.tandfonline.com/page/terms-and-conditions This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. The publisher does not give any warranty express or implied or make any representation that the contents will be complete or accurate or up to date. The accuracy of any instructions, formulae, and drug doses should be independently verified with primary sources. The publisher shall not be liable for any loss, actions, claims, proceedings, demand, or costs or damages whatsoever or howsoever caused arising directly or indirectly in connection with or arising out of the use of this material.
    [Show full text]
  • Table 4: Protective Action Criteria (PAC) Rev 27 Based on Applicable 60-Minute Aegls, Erpgs, Or Teels
    Table 4: Protective Action Criteria (PAC) Rev 27 based on applicable 60-minute AEGLs, ERPGs, or TEELs. The chemicals are listed in 3 alphabetical order and the values are presented in mg/m . February 2012 Table 4 is an alphabetical list of the chemical substances and their corresponding PAC values in mass per unit volume (mg/m3). The conversion of ppm to mg/m3 was carried out assuming normal temperature and pressure, 25°C and 760 mm Hg. The columns presented in Table 4 provide the following information: Heading Definition No. The ordered numbering of the chemicals as they appear in this alphabetical listing Chemical Name The name of the chemical substance submitted to the PAC development team CASRN The Chemical Abstracts Service Registry Number1 for this chemical PAC-1 Based on the applicable AEGL-1, ERPG-1, or TEEL-1 value PAC-2 Based on the applicable AEGL-2, ERPG-2, or TEEL-2 value PAC-3 Based on the applicable AEGL-3, ERPG-3, or TEEL-3 value Chemicals for which AEGLs are available have their chemical name, CASRN, and AEGL values displayed in a bolded and larger font. Chemicals for which ERPGs are available, but not AEGLs, have their chemical name, CASRN, and ERPG values displayed in a bolded font. Chemicals for which TEELs are available, but no AEGLs or ERPGs, have their chemical name, CASRN, and values displayed using a regular font. Additional information on PAC values and TEEL values and links to other sources of information is provided on the Subcommittee on Consequence Assessment and Protective Actions (SCAPA) webpage at: http://orise.orau.gov/emi/scapa/teels.htm.
    [Show full text]