当前位置： SCI文献检索 > BIOORGANIC & MEDICINAL CHEMISTRY LETTERS期刊下所有文献 > Anti-HBV active constituents from Piper longum.

Anti-HBV active constituents from Piper longum.

Abstract：

:In the screening search for Hepatitis B virus inhibitory agents from medicinal plants, the ethanol extract of Piper longum Linn. was found to possess superior anti-HBV activity in vitro. Bioassay-guided fractionation coupled with repeated purification resulted in the isolation of four new compounds, involving two new glycosides longumosides A (1) and B (2) and two new amide alkaloids erythro-1-[1-oxo-9(3,4-methylenedioxyphenyl)-8,9-dihydroxy-2E-nonenyl]-piperidine (3), threo-1-[1-oxo-9(3,4-methylenedioxyphenyl)-8,9-dihydroxy-2E-nonenyl]-piperidine (4), as well as two compounds 3β,4α-dihydroxy-2-piperidinone (5), 5,6-dihydro-2(1H)-pyridinone (6) from natural source for the first time. The structures of the four new compounds were determined by extensive analyses of the MS, IR, 1D and 2D NMR data. Besides, the compounds 2-6, together with the known compounds 7-11 obtained previously, were assayed for their anti-HBV activity by using Hep G 2.2.15 cell line in vitro. Results suggested the compound piperine (7) possessed remarkable inhibitory HBV activity, against the secretion of hepatitis B virus surface antigen (HBsAg) and hepatitis B virus e antigen (HBeAg) with the Selectivity Index (SI) values of 15.7 and 16.8, respectively.

journal_name

Bioorg Med Chem Lett

journal_title

Bioorganic & medicinal chemistry letters

authors

Jiang ZY,Liu WF,Zhang XM,Luo J,Ma YB,Chen JJ

doi

10.1016/j.bmcl.2013.01.118

subject

Has Abstract

pub_date

2013-04-01 00:00:00

pages

2123-7

issue

7

eissn

0960-894X

issn

1464-3405

pii

S0960-894X(13)00151-0

journal_volume

23

pub_type

杂志文章

相关文献

BIOORGANIC & MEDICINAL CHEMISTRY LETTERS文献大全
  • Discovery of (E)-1-amino-4-phenylbut-3-en-2-ol derivatives as novel neuraminidase inhibitors.

    abstract：:Neuraminidase has been considered as an important target for designing agents against influenza viruses. In a discovery of anti-influenza agents with epigoitrin as the initial lead compound, a series of 1-amino-2-alkanols were synthesized and biologically evaluated. The in vitro evaluation indicated that (E)-1-amino-4...

    journal_title：Bioorganic & medicinal chemistry letters

    pub_type： 杂志文章

    doi：10.1016/j.bmcl.2018.05.002

    authors： Lu C,Yin Y,Meng F,Dun Y,Pei K,Wang C,Xu X,Wu F

    更新日期：2018-06-15 00:00:00

  • Discovery, SAR, and X-ray structure of novel biaryl-based dipeptidyl peptidase IV inhibitors.

    abstract：:The discovery, SAR, and X-ray crystal structure of novel biarylaminoacyl-(S)-2-cyano-pyrrolidines and biarylaminoacylthiazolidines as potent inhibitors of dipeptidyl peptidase IV (DPP IV) are reported. ...

    journal_title：Bioorganic & medicinal chemistry letters

    pub_type： 杂志文章

    doi：10.1016/j.bmcl.2005.09.037

    authors： Qiao L,Baumann CA,Crysler CS,Ninan NS,Abad MC,Spurlino JC,Desjarlais RL,Kervinen J,Neeper MP,Bayoumy SS,Williams R,Deckman IC,Dasgupta M,Reed RL,Huebert ND,Tomczuk BE,Moriarty KJ

    更新日期：2006-01-01 00:00:00

  • Substituted 4-anilino-7-phenyl-3-quinolinecarbonitriles as Src kinase inhibitors.

    abstract：:A series of substituted 4-anilino-7-phenyl-3-quinolinecarbonitriles has been prepared as Src kinase inhibitors. Optimal activity is observed with compounds that have basic amines attached via the para position of the 7-phenyl ring, and a hydrogen atom at the C-6 position. The best compounds are low nanomolar inhibitor...

    journal_title：Bioorganic & medicinal chemistry letters

    pub_type： 杂志文章

    doi：10.1016/s0960-894x(02)00577-2

    authors： Berger D,Dutia M,Powell D,Wissner A,DeMorin F,Raifeld Y,Weber J,Boschelli F

    更新日期：2002-10-21 00:00:00

  • Discovery of potent selective bioavailable phosphodiesterase 2 (PDE2) inhibitors active in an osteoarthritis pain model. Part II: optimization studies and demonstration of in vivo efficacy.

    abstract：:Selective phosphodiesterase 2 (PDE2) inhibitors are shown to have efficacy in a rat model of osteoarthritis (OA) pain. We identified potent, selective PDE2 inhibitors by optimizing residual PDE2 activity in a series of phosphodiesterase 4 (PDE4) inhibitors, while minimizing PDE4 inhibitory activity. These newly design...

    journal_title：Bioorganic & medicinal chemistry letters

    pub_type： 杂志文章

    doi：10.1016/j.bmcl.2013.03.082

    authors： Plummer MS,Cornicelli J,Roark H,Skalitzky DJ,Stankovic CJ,Bove S,Pandit J,Goodman A,Hicks J,Shahripour A,Beidler D,Lu XK,Sanchez B,Whitehead C,Sarver R,Braden T,Gowan R,Shen XQ,Welch K,Ogden A,Sadagopan N,Baum H

    更新日期：2013-06-01 00:00:00

  • Covalent binding of the 13C-labeled skin sensitizers 5-chloro-2-methylisothiazol-3-one (MCI) and 2-methylisothiazol-3-one (MI) to a model peptide and glutathione.

    abstract：:The reactivity of 4-[13C]- and 5-[13C]-5-chloro-2-methylisothiazol-3-one (MCI) and 2-methylisothiazol-3-one (MI) towards a model peptide and glutathione was followed by 13C and 1H[13C] NMR spectroscopy. Both molecules were found to react with GSH but in addition MCI was found to react with histidine and lysine to form...

    journal_title：Bioorganic & medicinal chemistry letters

    pub_type： 杂志文章

    doi：10.1016/j.bmcl.2003.11.002

    authors： Alvarez-Sánchez R,Basketter D,Pease C,Lepoittevin JP

    更新日期：2004-01-19 00:00:00

  • A regiospecific synthesis of a series of 1-sulfonyl azepinoindoles as potent 5-HT6 ligands.

    abstract：:A regiospecific synthesis of a series of 1-sulfonyl azepinoindoles as potent 5-HT6 ligands is reported. ...

    journal_title：Bioorganic & medicinal chemistry letters

    pub_type： 杂志文章

    doi：10.1016/j.bmcl.2008.06.030

    authors： Liu KG,Lo JR,Comery TA,Zhang GM,Zhang JY,Kowal DM,Smith DL,Di L,Kerns EH,Schechter LE,Robichaud AJ

    更新日期：2008-07-15 00:00:00

  • Synthesis and biological study of medicinally important Mannich bases derived from 4-(dimethylamino)-1,4,4a,5,5a,6,11,12a-octahydro-3,6,10,12,12a pentahydroxy naphthacene carboxamide.

    abstract：:The paper describes synthesis and antibacterial study of biologically active Mannich bases of carboxamide derivative employing Mannich reaction of 4-(dimethylamino)-1,4,4a,5,5a,6,11,12a-octahydro-3,6,10,12,12a pentahydroxy naphthacene carboxamide with various sulfonamides/secondary amines . They were analysed by eleme...

    journal_title：Bioorganic & medicinal chemistry letters

    pub_type： 杂志文章

    doi：10.1016/j.bmcl.2006.11.001

    authors： Joshi S,Manikpuri AD,Tiwari P

    更新日期：2007-02-01 00:00:00

  • Design and synthesis of a tetrahydropyran-based inhibitor of mammalian ribonucleotide reductase.

    abstract：:A tetrahydropyran-based inhibitor (2) of mammalian ribonucleotide reductase (mRR) has been designed and synthesized based on the heptapeptide, N-AcFTLDADF (1), corresponding to the C-terminus of the R2 subunit of mRR. Inhibition studies revealed that 2 is indeed a competent inhibitor, albeit less potent than 1. ...

    journal_title：Bioorganic & medicinal chemistry letters

    pub_type： 杂志文章

    doi：10.1016/s0960-894x(98)00575-7

    authors： Smith AB 3rd,Sasho S,Barwis BA,Sprengeler P,Barbosa J,Hirschmann R,Cooperman BS

    更新日期：1998-11-17 00:00:00

  • Combinatorial synthesis of SSAO inhibitors using sonogashira coupling: SAR of aryl propargylic amines.

    abstract：:The structure-activity relationships for semicarbazide-sensitive amine oxidase (SSAO) inhibitors based on arylpropynylamines was investigated using solution-phase combinatorial Sonogashira coupling. The results suggest that binding to the active site occurs by coordination of the amine to the proximal copper(II) and f...

    journal_title：Bioorganic & medicinal chemistry letters

    pub_type： 杂志文章

    doi：10.1016/s0960-894x(01)00506-6

    authors： Conn C,Shimmon R,Cordaro F,Hargraves TL,Ibrahim P

    更新日期：2001-10-08 00:00:00

  • Novel progesterone receptor modulators: 4-aryl-phenylsulfonamides.

    abstract：:We have developed a new series of progesterone receptor modulators based upon the 4-aryl-phenylsulfonamide. Initial work in the series afforded potent compounds with good properties, however an advanced intermediate proved to be genotoxic in a non-GLP Ames assay following metabolic activation. We subsequently solved t...

    journal_title：Bioorganic & medicinal chemistry letters

    pub_type： 杂志文章

    doi：10.1016/j.bmcl.2012.09.077

    authors： McComas C,Cohen J,Huselton C,Marella M,Melenski E,Mugford C,Slayden O,Winneker R,Wrobel J,Yudt MR,Fensome A

    更新日期：2012-12-01 00:00:00

  • A new selective fluorescent probe based on tamoxifen.

    abstract：:Developing targeted validation probes that can interrogate biology is of interest for both chemists and biologists. The synthesis of suitable compounds provides a means for avoiding the costly labeling of cells with specific antibodies and the bias associated with the interpretation of biological validation experiment...

    journal_title：Bioorganic & medicinal chemistry letters

    pub_type： 杂志文章

    doi：10.1016/j.bmcl.2016.09.028

    authors： Ho LA,Thomas E,McLaughlin RA,Flematti GR,Fuller RO

    更新日期：2016-10-15 00:00:00

  • Syntheses of certain 3-aryl-2-propenoates and evaluation of their cytotoxicity.

    abstract：:A series of 3-aryl-2-propenoates including cinnamates, (E)-methyl/ethyl 3-[2-(1,4-dimethoxy-5,8-dione)naphthalenyl]-2-propenoates (8ba, 8bb) and (E)-methyl/ethyl 3-[2-(1,4-dihydroxy-9,10-dione)anthracenyl]-2-propenoates (9aa,9ab) was synthesized and evaluated for antitumor cytotoxicity. It was found that the ortho- or...

    journal_title：Bioorganic & medicinal chemistry letters

    pub_type： 杂志文章

    doi：10.1016/s0960-894x(01)00165-2

    authors： Nam NH,You YJ,Kim Y,Hong DH,Kim HM,Ahn BZ

    更新日期：2001-05-07 00:00:00

  • Highly potent activity of isopulegol-derived substituted octahydro-2H-chromen-4-ols against influenza A and B viruses.

    abstract：:A set of (-)-isopulegol derived octahydro-2H-chromen-4-ols was synthesized and evaluated in vitro for antiviral activity against panel of reference influenza virus strains differing in subtype, origin (human or avian) and drug resistance. Compound (4R)-11a produced via one-pot synthesis by interaction between (-)-isop...

    journal_title：Bioorganic & medicinal chemistry letters

    pub_type： 杂志文章

    doi：10.1016/j.bmcl.2018.04.057

    authors： Ilyina IV,Zarubaev VV,Lavrentieva IN,Shtro AA,Esaulkova IL,Korchagina DV,Borisevich SS,Volcho KP,Salakhutdinov NF

    更新日期：2018-06-15 00:00:00

  • Identification of prostaglandin D2 receptor antagonists based on a tetrahydropyridoindole scaffold.

    abstract：:A new series of indole-based antagonists of the PGD(2) receptor subtype 1 (DP1 receptor) was identified and the progress of the structure-activity relationship study to the identification of potent and selective antagonists is presented. Selective DP1 antagonists with high potency and selectivity were prepared. Of par...

    journal_title：Bioorganic & medicinal chemistry letters

    pub_type： 杂志文章

    doi：10.1016/j.bmcl.2008.03.015

    authors： Beaulieu C,Guay D,Wang Z,Leblanc Y,Roy P,Dufresne C,Zamboni R,Berthelette C,Day S,Tsou N,Denis D,Greig G,Mathieu MC,O'Neill G

    更新日期：2008-04-15 00:00:00

  • First synthesis of separable isomeric testosterone dimers showing differential activities on prostate cancer cells.

    abstract：:The synthesis of two separable isomeric testosterone dimers is reported. The dimers are made from testosterone in a 5 step sequence and with 36% overall yield. The key dimerization step was performed using Hoveyda-Grubb's metathesis catalysts on 7alpha-allyltestosterone with 75% yield. The synthesis led to separable i...

    journal_title：Bioorganic & medicinal chemistry letters

    pub_type： 杂志文章

    doi：10.1016/j.bmcl.2010.02.077

    authors： Bastien D,Leblanc V,Asselin E,Bérubé G

    更新日期：2010-04-01 00:00:00

  • Vialinin A and thelephantin G, potent inhibitors of tumor necrosis factor-α production, inhibit sentrin/SUMO-specific protease 1 enzymatic activity.

    abstract：:Several p-terphenyl compounds have been isolated from the edible Chinese mushroom Thelephora vialis. Vialinin A, a p-terphenyl compound, strongly inhibits tumor necrosis factor-α production and release. Vialinin A inhibits the enzymatic activity of ubiquitin-specific peptidase 5, one of the target molecules in RBL-2H3...

    journal_title：Bioorganic & medicinal chemistry letters

    pub_type： 杂志文章

    doi：10.1016/j.bmcl.2016.07.051

    authors： Yoshioka Y,Namiki D,Makiuchi M,Sugaya K,Onose J,Ashida H,Abe N

    更新日期：2016-09-01 00:00:00

  • Discovery and optimization of a biphenylacetic acid series of prostaglandin D2 receptor DP2 antagonists with efficacy in a murine model of allergic rhinitis.

    abstract：:Biphenylacetic acid (5) was identified through a library screen as an inhibitor of the prostaglandin D(2) receptor DP2 (CRTH2). Optimization for potency and pharmacokinetic properties led to a series of selective CRTH2 antagonists. Compounds demonstrated potency in a human DP2 binding assay and a human whole blood eos...

    journal_title：Bioorganic & medicinal chemistry letters

    pub_type： 杂志文章

    doi：10.1016/j.bmcl.2011.01.024

    authors： Scott JM,Baccei C,Bain G,Broadhead A,Evans JF,Fagan P,Hutchinson JH,King C,Lorrain DS,Lee C,Prasit P,Prodanovich P,Santini A,Stearns BA

    更新日期：2011-11-01 00:00:00

  • Design and synthesis of new 2-substituted-5-(2-benzylthiophenyl)-1,3,4-oxadiazoles as benzodiazepine receptor agonists.

    abstract：:A series of new 2-substituted-5-(2-benzylthiophenyl)-1,3,4-oxadiazoles was designed and synthesized as anticonvulsant agents. Conformational analysis and superimposition of energy minima conformers of the designed molecules on estazolam, a known benzodiazepine receptor agonist, revealed that the main proposed benzodia...

    journal_title：Bioorganic & medicinal chemistry letters

    pub_type： 杂志文章

    doi：10.1016/j.bmcl.2005.04.018

    authors： Zarghi A,Faizi M,Shafaghi B,Ahadian A,Khojastehpoor HR,Zanganeh V,Tabatabai SA,Shafiee A

    更新日期：2005-06-15 00:00:00

  • Synthesis and biological evaluation of imidazole-based small molecule antagonists of the melanocortin 4 receptor (MC4-R).

    abstract：:A novel series of imidazole-based small molecule antagonists of the melanocortin 4 receptor (MC4-R) is reported. Members of this series have been identified, which exhibit sub-micromolar binding affinity for the MC4-R, functional potency <100nM, and good oral exposure in rat. Antagonists of the MC4-R are potentially u...

    journal_title：Bioorganic & medicinal chemistry letters

    pub_type： 杂志文章

    doi：10.1016/j.bmcl.2004.05.003

    authors： Marsilje TH,Roses JB,Calderwood EF,Stroud SG,Forsyth NE,Blackburn C,Yowe DL,Miao W,Drabic SV,Bohane MD,Daniels JS,Li P,Wu L,Patane MA,Claiborne CF

    更新日期：2004-07-16 00:00:00

  • Design, synthesis, and structure-activity relationships of indole-3-heterocycles as agonists of the CB1 receptor.

    abstract：:Novel indole-3-heterocycles were designed and synthesized and found to be potent CB1 receptor agonists. Starting from a microsomally unstable lead 1, a bioisostere approach replacing a piperazine amide was undertaken. This was found to be a good strategy for improving stability both in vitro and in vivo. This led to t...

    journal_title：Bioorganic & medicinal chemistry letters

    pub_type： 杂志文章

    doi：10.1016/j.bmcl.2010.10.093

    authors： Morrison AJ,Adam JM,Baker JA,Campbell RA,Clark JK,Cottney JE,Deehan M,Easson AM,Fields R,Francis S,Jeremiah F,Keddie N,Kiyoi T,McArthur DR,Meyer K,Ratcliffe PD,Schulz J,Wishart G,Yoshiizumi K

    更新日期：2011-01-01 00:00:00

  • Aminothiazoles as γ-secretase modulators.

    abstract：:We herein report the discovery of a new γ-secretase modulator class with an aminothiazole core starting from a HTS hit (3). Synthesis and SAR of this series are discussed. These novel compounds demonstrate moderate to good in vitro potency in inhibiting amyloid beta (Aβ) peptide production. Overall γ-secretase is not ...

    journal_title：Bioorganic & medicinal chemistry letters

    pub_type： 杂志文章

    doi：10.1016/j.bmcl.2011.08.060

    authors： Lübbers T,Flohr A,Jolidon S,David-Pierson P,Jacobsen H,Ozmen L,Baumann K

    更新日期：2011-11-01 00:00:00

  • New arylalkanones from Horsfieldia macrobotrys, effective antidiabetic agents concomitantly inhibiting α-glucosidase and free radicals.

    abstract：:In search of effective antidiabetic agents having therapeutic effect by inhibiting α-glucosidase and preventive effect by scavenging free radicals, Horsfieldia macrobotrys showed promising bioactivity required for the proposed criteria. Bioassay-guided isolation of the stem bark extract resulted in two new arylalkanon...

    journal_title：Bioorganic & medicinal chemistry letters

    pub_type： 杂志文章

    doi：10.1016/j.bmcl.2015.08.069

    authors： Ramadhan R,Phuwapraisirisan P

    更新日期：2015-10-15 00:00:00

  • Native chemical ligation derived method for recombinant peptide/protein C-terminal amidation.

    abstract：:C-terminal amidation is often a requisite structural feature for peptide hormone bio-activity. We report a chemical amidation method that converts peptide/protein thioesters into their corresponding C-terminal amides. The peptide/protein thioester is treated with 1-(2,4-dimethoxyphenyl)-2-mercaptoethyl auxiliary (1b) ...

    journal_title：Bioorganic & medicinal chemistry letters

    pub_type： 杂志文章

    doi：10.1016/j.bmcl.2013.06.095

    authors： Sun C,Luo G,Neravetla S,Ghosh SS,Forood B

    更新日期：2013-09-15 00:00:00

  • Novel zinc finger nuclease created by combining the Cys(2)His(2)- and His(4)-type zinc finger domains.

    abstract：:To improve the DNA hydrolytic activity of the zinc finger nuclease, we have created a new artificial zinc finger nuclease (ZWH4) by connecting two distinct zinc finger domains possessing different types of Zn(II) binding sites (Cys(2)His(2)- and His(4)-types). The overall fold of ZWH4 is similar to that of the wild-ty...

    journal_title：Bioorganic & medicinal chemistry letters

    pub_type： 杂志文章

    doi：10.1016/j.bmcl.2009.03.088

    authors： Negi S,Umeda Y,Masuyama S,Kano K,Sugiura Y

    更新日期：2009-05-15 00:00:00

  • Design and synthesis of phosphotyrosine mimetics.

    abstract：:Selective inhibitors of protein tyrosine phosphatases (PTPases) are of great interest as therapeutic agents and research tools. Several phenylalanine derivatives (1, 2) designed as phosphotyrosine mimetics or irreversible active site inhibitors were successfully synthesized, then incorporated into a combinatorial libr...

    journal_title：Bioorganic & medicinal chemistry letters

    pub_type： 杂志文章

    doi：10.1016/s0960-894x(03)00253-1

    authors： Yan Z,Kahn M,Qabar M,Urban J,Kim HO,Blaskovich MA

    更新日期：2003-06-16 00:00:00

  • 1,2,3-Triazole fused with pyridine/pyrimidine as new template for antimicrobial agents: Regioselective synthesis and identification of potent N-heteroarenes.

    abstract：:The 1,2,3-triazole ring fused with pyridine/pyrimidine was explored as new template for the identification of potential antimicrobial agents. The regioselective synthesis of these pre-designed N-heteroarenes was achieved via exploring the application of Buchwald's strategy (i.e. C-N bond formation/reduction/diazotizat...

    journal_title：Bioorganic & medicinal chemistry letters

    pub_type： 杂志文章

    doi：10.1016/j.bmcl.2018.09.021

    authors： Marepu N,Yeturu S,Pal M

    更新日期：2018-11-01 00:00:00

  • A practical deuterium-free NMR method for the rapid determination of 1-octanol/water partition coefficients of pharmaceutical agents.

    abstract：:A simple and rapid NMR method is described to determine the logP of pharmaceutical agents. This method is highly versatile and efficient, because it does not require the use of deuterated solvents or the addition of any internal/external standards to the sample. We demonstrate that logP can be accurately measured usin...

    journal_title：Bioorganic & medicinal chemistry letters

    pub_type： 杂志文章

    doi：10.1016/j.bmcl.2010.08.145

    authors： Mo H,Balko KM,Colby DA

    更新日期：2010-11-15 00:00:00

  • Synthesis of 14-deoxy-11,12-didehydroandrographolide analogues as potential cytotoxic agents for cholangiocarcinoma.

    abstract：:A series of 14-deoxy-11,12-didehydroandrographolide analogues were synthesized from naturally occurring andrographolide and their cytotoxicity evaluated against nine cancer cell lines including cholangiocarcinoma. Analogues 5a and 5b exhibited the most potent cytotoxicity with ED50s of 3.37 and 3.08 μM on KKU-M213 cel...

    journal_title：Bioorganic & medicinal chemistry letters

    pub_type： 杂志文章

    doi：10.1016/j.bmcl.2017.10.063

    authors： Sombut S,Bunthawong R,Sirion U,Kasemsuk T,Piyachaturawat P,Suksen K,Suksamrarn A,Saeeng R

    更新日期：2017-12-01 00:00:00

  • High throughput screening identifies novel inhibitors of Escherichia coli dihydrofolate reductase that are competitive with dihydrofolate.

    abstract：:This communication describes the high-throughput screen of a diverse library of 50,000 small molecules against Escherichia coli dihydrofolate reductase to detect inhibitors. Sixty-two compounds were identified as having significant inhibitory activity against the enzyme. Secondary screening of these revealed twelve mo...

    journal_title：Bioorganic & medicinal chemistry letters

    pub_type： 杂志文章

    doi：10.1016/s0960-894x(03)00480-3

    authors： Zolli-Juran M,Cechetto JD,Hartlen R,Daigle DM,Brown ED

    更新日期：2003-08-04 00:00:00

  • Pyrrolo[2,3-h]quinolinones: synthesis and photochemotherapic activity.

    abstract：:A series of derivatives of the new ring system pyrrolo[2,3-h]quinoline-2-one was synthesized and evaluated as photoreagents toward cultured human tumor cells. Remarkable phototoxycity resulted for some derivatives, especially those bearing the phenyl group at the 7-position. ...

    journal_title：Bioorganic & medicinal chemistry letters

    pub_type： 杂志文章

    doi：10.1016/s0960-894x(03)00529-8

    authors： Barraja P,Diana P,Lauria A,Montalbano A,Almerico AM,Dattolo G,Cirrincione G,Viola G,Dall'Acqua F

    更新日期：2003-08-18 00:00:00