What's the difference between pentamethylene and tetrahydropyran?
Pentamethylene
Definition:
(n.) A hypothetical hydrocarbon, C5H10, metameric with the amylenes, and the nucleus of a large number of derivatives; -- so named because regarded as composed of five methylene residues. Cf. Trimethylene, and Tetramethylene.
Example Sentences:
(1) [1-(beta,beta-Pentamethylene-beta-mercaptopropionic acid),2-(O-ethyl)-D- tyrosine,4-valine,9-desglycine]arginine-vasopressin (SK&F 101926, 1), a potent in vivo and in vitro vasopressin V2 receptor antagonist, was recently tested in human volunteers and shown to be a full antidiuretic agonist.
(2) After administration of subconvulsant dose of pentamethylene tetrazole (PMT) PGF2 alpha increases sharply and rapidly declines subsequently, whereas the elevation of TXB2 is smaller but of longer duration.
(3) spectra with those of 1-nicotinoyl and 1-isonicotinoyl-4,5-pentamethylene-5-hydroxy-2-pyrazoline, obtained by reaction of 2-hydroxymethylenecycloheptanone with nicotinoyl and isonicotinoylhydrazide, respectively.
(4) A pentamethylene chain was used to covalently link the 3'-phosphate of oligothymidylates to the 9-amino group of an acridine derivative.
(5) The isozymes differ in their inhibition by various 4-azasteroids with the type 2 isozyme showing exquisite sensitivity (Ki = 40 pM) to 21,21-pentamethylene-4-aza-5 alpha-pregn-1-ene-3,20-dione.
(6) Using the effective dosages determined from the morning studies, repeated injections of either OT, AVP or their specific antagonists MPOMeOVT [( 1-(beta-mercapto-beta, beta-cyclopentamethylene propanoic acid), 2-(O-methyl)tyrosine, 8-ornithine]-vasotocin) and d (CH2)5Tyr(Me)AVP ([1-(beta-mercapto-beta, beta-cyclo-pentamethylene propionic acid), 2-(O-methyl)tyrosine, 8-arginine]-vasopressin), were given hourly between 1300 to 1800 h and blood samples were obtained hourly from 1100 to 1900 h. It was found that either OT or AVP significantly reduced the afternoon PRL surge, while their antagonists were not as effective.
(7) The COSY and NOESY connectivities allowed us to assign all the proton resonances of the bases, the sugars (except the overlapping 5'-5'' resonances), the acridine, and the pentamethylene chain.
(8) We report twelve analogues of [Pmp1,D-Trp2,Arg8]oxytocin, ANTAG (Pmp = beta, beta-pentamethylene-beta-mercaptopropionic acid), which is a potent antagonist (pA2 = 7.77) of the uterotonic effect of oxytocin (OT) in rats, as measured in a uterotonic assay.
(9) A stronger antiphytoviral effect was observed for N-phenyl, N',N'-pentamethylene thiourea, as well as N-methyl thiourea.
(10) The synteshis of 2-phenyl-4,4-pentamethylene-morpholinium bromide (VII) from the hydrogenation of either the 2-phenyl or 2-p-bromophenyl-2,3-dehydromorpholinium derivativies (VI) is also reported.
(11) The V2 antagonist [1-(beta-mercapto-beta,beta-pentamethylene-proprionic acid), 2-d-isoleucine,4-isoleucine]arginine-vasopressin blocked the effects of clonidine but not 2,6-DMC.
(12) Octyl methyl-, butyl methyl- and pentamethylene sulfide react with about 50% of oxidized cytochrome P-450 in liver microsomes from phenobarbital-pretreated rats by formation of optical difference spectra with maxima at 435 and 552 nm and concomitant shifts in the electron paramagnetic resonance spectrum.
(13) An oligo-[alpha]-deoxynucleotide of sequence (5')d(TCTAAACTC) (3') was synthesized using the alpha-anomers of deoxynucleosides and its 5'-phosphate was covalently linked to a 9-amino acridine derivative via a pentamethylene linker.
(14) The selectivity was not related to the affinity and some weakly active compounds retained appreciable selectivity but no compound had greater selectivity than 4-DAMP methobromide or pentamethylene bis-(4-diphenylacetoxy-N-methylpiperidinium) bromide.
(15) Hexamethylene bisacetamide and the closely related pentamethylene bisacetamide were synthesized with radioactive labels in various portions of the molecule and the uptake, metabolism, and intracellular distribution determined.
(16) The NOE connectivities observed between the protons of the bases or of the sugars and the protons of the dye and of the pentamethylene chain led us to propose a model involving an equilibrium between two families of configurations.
(17) Straight-chain carboxylic acids where the carboxyl group was separated from the acetophenone moiety by varying numbers of methylenes were evaluated, and maximum activity was obtained with the pentamethylene acid (6).
(18) The oligodeoxynucleotide d(TATC) was covalently attached to the 9-amino group of 2-methoxy-6-chloro-9-aminoacridine (Acr) through its 3'-phosphate via a pentamethylene linker (m5).
(19) Other convulsant drugs which failed to block cortical inhibition included picrotoxin, pentamethylene tetrazole, thiosemicarbazide, longchain omega-amino acids and morphine.5.
(20) The analogues with long-chain beta-alkylation (diethyl and pentamethylene) and the linear antagonist photolabel showed significantly less affinity.
Tetrahydropyran
Definition:
Example Sentences:
(1) Esters at C9 were synthesized by acylation of dinoprost 11,15-bis(tetrahydropyran-2-yl)ether followed by acid-catalyzed protective group removal.
(2) Galtamycinone was shown to be 1,4,6-trioxy-10 [4 (e), 5 (e)-dioxy-6 (e)-methyl-tetrahydropyran-2(e)-yl]-8-methyl tetracendion-5,12.
(3) Their structures were determined as tetrahydropyran derivatives with an alkenyl side chain on the basis of their spectroscopic and physico-chemical properties.
(4) These resulting 2',5'- and 3',5'-diacylates were further derived, by the known method, into the 3'- and 2'-O-tetrahydropyran-2-yl ribonucleoside derivatives, respectively, with which some ribonucleotide oligomer syntheses have been performed.
(5) The hydroxy group in methyl ricinoleate was protected (O-tetrahydropyran-2'-yl) prior to dichlorocyclopropanation of the ethylenic bond.
(6) A tetrahydropyran ring-containing fatty acid-combined taurine (tetrathermoyltaurine) was found in the taurolipid fraction of Tetrahymena thermophila.
(7) Bisnorcholyl aldehyde was prepared from cholic acid and converted into the cholestane-pentols by a Grignard reaction with 3-methyl-3-(tetrahydropyran-2-yloxy)-butynylmagnesium bromide followed by hydrogenation and acid hydrolysis.
(8) Six-membered lactone and tetrahydropyran analogues of platelet-activating factor (PAF), 4-11, and related antagonistic derivatives 41-46 were synthesized.
(9) we identified a new series of antifungals having a tetrahydropyran skeleton with an alkenyl side chain.
(10) The tetrahydropyran is in a chair conformation with the furanone ring equatorial.
(11) In polymers of tetrahydrofurfuryl methacrylate and acrylate, tetrahydropyranyl and tetrahydropyran-2-ylmethyl methacrylate, fewer than 1% monomer units were involved in cross-linking and hence ring-opening reactions.
(12) Reaction of 8-bromo-2',3'-O-isopropylidene-5'-O-(tetrahydropyran-2-yl) adenosine (Ib) with lithium 2-(tetrahydropyran-2-yloxy) ethoxide, followed by removal of the tetrahydropyran-2-yl groups, afforded 8-(2''-hydroxyethoxy)-2',3'-O-isopropylideneadenosine (II).
(13) We therefore decided to eliminate most of the secondary hydroxyl groups and to compare the distribution properties of simple sugar analogs based on tetrahydropyran.
(14) The spiro attachment of an epoxide group to a tetrahydropyran ring in the trichothecene mycotoxins has prompted this study of the mutagenicity and alkylation rates of the trichothecene, anguidine, and 5 related model oxaspiro compounds.
(15) A marked change in mass spectral fragmentation compared to aurodox and 1H NMR couplings indicated the absence of the hydroxyl at position 30 of aurodox (position 3 of the tetrahydropyran).
(16) These are of 2-hydroxy-, 3-hydroxy-, and 2-methyl-4-hydroxytamoxifen and of 1-(4-methoxyphenyl)-2-phenyl-1-[(tetrahydropyran-2-yloxy)phenyl]-1 -butanol, the synthetic precursor to 2-hydroxytamoxifen.
(17) The analytical method used allowed the identification, among the various compounds, of a family of tetrahydropyran homologues with an aminic chain, phthalates, thiophene and pyridine derivatives.
(18) However, when silylated DTPC was reacted with 2-chlorotetrahydropyran, two tetrahydropyran-2-yl compounds were obtained, and these were shown to be positional isomers on the basis of 1H NMR and UV data.
(19) Free hydroxyl groups are transformed into tetrahydropyran ethers, deacylated by dimsyl sodium, methylated and the sugar derivatives are hydrolyzed.
(20) These faster solvents were cyclic ethers (tetrahydrofuran [THF], methyl tetrahydrofuran [MTHF], tetrahydropyran [THP], methyl tetrahydropyran [MTHP], and possibly dimethyl tetrahydrofuran [DMTHF]) and limonene.