51
|
Abstract
Hydrazino depsipeptides, a new class of backbone extended peptidomimetics were prepared by the Passerini reaction of α-hydrazino acids, carbonyl compounds and isocyanides.
Collapse
Affiliation(s)
- Josipa Suć
- Division of Organic Chemistry and Biochemistry
- Ruđer Bošković Institute
- 10000 Zagreb
- Croatia
| | - Danijela Barić
- Division of Physical Chemistry
- Ruđer Bošković Institute
- 10 000 Zagreb
- Croatia
| | - Ivanka Jerić
- Division of Organic Chemistry and Biochemistry
- Ruđer Bošković Institute
- 10000 Zagreb
- Croatia
| |
Collapse
|
52
|
Zhang Z, Zhang L, Chen Q, Lu T, Zhou Q. Synthesis of functionalized tetrahydropyridazines via catalyst-free self [4 + 2] cycloaddition of in situ generated 1,2-diaza-1,3-dienes. RSC Adv 2016. [DOI: 10.1039/c6ra13985j] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
An efficient method for the synthesis of structurally diverse functionalized tetrahydropyridazines via self [4 + 2] cycloaddition of in situ generated 1,2-diaza-1,3-dienes was developed, which may play an important role in drug discovery.
Collapse
Affiliation(s)
- Zhimin Zhang
- State Key Laboratory of Natural Medicines
- Department of Organic Chemistry
- China Pharmaceutical University
- Nanjing
- P. R. China
| | - Li Zhang
- State Key Laboratory of Natural Medicines
- Department of Organic Chemistry
- China Pharmaceutical University
- Nanjing
- P. R. China
| | - Qingqing Chen
- State Key Laboratory of Natural Medicines
- Department of Organic Chemistry
- China Pharmaceutical University
- Nanjing
- P. R. China
| | - Tao Lu
- State Key Laboratory of Natural Medicines
- Department of Organic Chemistry
- China Pharmaceutical University
- Nanjing
- P. R. China
| | - Qingfa Zhou
- State Key Laboratory of Natural Medicines
- Department of Organic Chemistry
- China Pharmaceutical University
- Nanjing
- P. R. China
| |
Collapse
|
53
|
Lee A, Kim H. Rhodium-Catalyzed Asymmetric 1,4-Addition of α,β-Unsaturated Imino Esters Using Chiral Bicyclic Bridgehead Phosphoramidite Ligands. J Am Chem Soc 2015; 137:11250-3. [DOI: 10.1021/jacs.5b07034] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Ansoo Lee
- Department of Chemistry, KAIST, Daejeon 34141, Korea
| | - Hyunwoo Kim
- Department of Chemistry, KAIST, Daejeon 34141, Korea
- Center for Nanomaterials and Chemical Reactions, Institute for Basic Science, Daejeon 34141, Korea
| |
Collapse
|
54
|
|
55
|
Manaviazar S, Stevenson PJ, Hale KJ. On the halogenation of N (1), N (2)-di- t -Boc-5-hydroxy-piperazic acid esters and the conformational preferences of their 5-halo-piperazic acid products. The importance of A 1,3 rotameric-strain in determining N (2)-acyl piperazic acid ring conformation. Tetrahedron Lett 2015. [DOI: 10.1016/j.tetlet.2015.04.062] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
56
|
Structure and Synthesis of Conformationally Constrained Molecules Containing Piperazic Acid. TOPICS IN HETEROCYCLIC CHEMISTRY 2015. [DOI: 10.1007/7081_2015_185] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
|
57
|
Yoshida M, Sekioka N, Izumikawa M, Kozone I, Takagi M, Shin-ya K, Doi T. Total Synthesis and Structure Elucidation of JBIR-39: A Linear Hexapeptide Possessing Piperazic Acid and γ-Hydroxypiperazic Acid Residues. Chemistry 2014; 21:3031-41. [DOI: 10.1002/chem.201406020] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Indexed: 11/08/2022]
|
58
|
Natural hydrazine-containing compounds: Biosynthesis, isolation, biological activities and synthesis. Bioorg Med Chem 2014; 22:6529-6544. [DOI: 10.1016/j.bmc.2014.10.011] [Citation(s) in RCA: 100] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Revised: 10/07/2014] [Accepted: 10/09/2014] [Indexed: 11/22/2022]
|
59
|
Liu B, Liu TY, Luo SW, Gong LZ. Asymmetric Hetero-Diels–Alder Reaction of Diazenes Catalyzed by Chiral Silver Phosphate: Water Participates in the Catalysis and Stereocontrol. Org Lett 2014; 16:6164-7. [DOI: 10.1021/ol503047s] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- Bin Liu
- Hefei National Laboratory
for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Tong-Yu Liu
- Hefei National Laboratory
for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Shi-Wei Luo
- Hefei National Laboratory
for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Liu-Zhu Gong
- Hefei National Laboratory
for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei 230026, China
| |
Collapse
|
60
|
Kang CW, Ranatunga S, Sarnowski MP, Del Valle JR. Solid-phase synthesis of tetrahydropyridazinedione-constrained peptides. Org Lett 2014; 16:5434-7. [PMID: 25295511 PMCID: PMC4201324 DOI: 10.1021/ol5026684] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
![]()
The
design and solid-phase synthesis of tetrahydropyridazine-3,6-dione
(Tpd) peptidomimetics derived from backbone-aminated peptides is reported.
The described protocol features the synthesis of chiral α-hydrazino
acids suitable for chemoselective incorporation into growing peptide
chains. Acid-catalyzed cyclization to form the Tpd ring during cleavage
affords the target peptidomimetics in good yield and purity. The scope
of Tpd incorporation is demonstrated through the synthesis of constrained
peptides featuring nucleophilic/electrophilic side chains and sterically
encumbered α-substituted hydrazino acid residues.
Collapse
Affiliation(s)
- Chang Won Kang
- Drug Discovery Department, H. Lee Moffitt Cancer Center and Research Institute , Tampa, Florida 33612, United States
| | | | | | | |
Collapse
|
61
|
Zhirov AM, Aksenov AV. Azodicarboxylates: synthesis and functionalization of organic compounds. RUSSIAN CHEMICAL REVIEWS 2014. [DOI: 10.1070/rc2014v083n06abeh004419] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
62
|
Handy EL, Totaro KA, Lin CP, Sello JK. Efficient and regiospecific syntheses of peptides with piperazic and dehydropiperazic acids via a multicomponent reaction. Org Lett 2014; 16:3488-91. [PMID: 24937740 DOI: 10.1021/ol501425b] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Peptides containing N2-acyl piperazic or 1,6-dehydropiperazic acids can be formed efficiently via a novel multicomponent reaction of 1,4,5,6-tetrahydropyridazines, isocyanides, and carboxylic acids. Remarkably, the reaction's induced intramolecularity can enable the regiospecific formation of products with N2-acyl piperazic acid, which counters the intrinsic and troublesome propensity for piperazic acids to react at N1 in acylations. The utility of the methodology is demonstrated in the synthesis of the bicyclic core of the interleukin-1β converting enzyme inhibitor, Pralnacasan.
Collapse
Affiliation(s)
- Emma L Handy
- Department of Chemistry, Brown University , 324 Brook Street, Providence, Rhode Island 02912, United States
| | | | | | | |
Collapse
|
63
|
Fernández J, Marín L, Alvarez-Alonso R, Redondo S, Carvajal J, Villamizar G, Villar CJ, Lombó F. Biosynthetic modularity rules in the bisintercalator family of antitumor compounds. Mar Drugs 2014; 12:2668-99. [PMID: 24821625 PMCID: PMC4052310 DOI: 10.3390/md12052668] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Revised: 04/09/2014] [Accepted: 04/11/2014] [Indexed: 12/05/2022] Open
Abstract
Diverse actinomycetes produce a family of structurally and biosynthetically related non-ribosomal peptide compounds which belong to the chromodepsipeptide family. These compounds act as bisintercalators into the DNA helix. They give rise to antitumor, antiparasitic, antibacterial and antiviral bioactivities. These compounds show a high degree of conserved modularity (chromophores, number and type of amino acids). This modularity and their high sequence similarities at the genetic level imply a common biosynthetic origin for these pathways. Here, we describe insights about rules governing this modular biosynthesis, taking advantage of the fact that nowadays five of these gene clusters have been made public (thiocoraline, triostin, SW-163 and echinomycin/quinomycin). This modularity has potential application for designing and producing novel genetic engineered derivatives, as well as for developing new chemical synthesis strategies. These would facilitate their clinical development.
Collapse
Affiliation(s)
- Javier Fernández
- Research Group BITTEN, Instituto Universitario de Oncología del Principado de Asturias (IUOPA), Universidad de Oviedo, C/Julián Clavería 7, Facultad de Medicina, Oviedo 33006, Spain.
| | - Laura Marín
- Research Group BITTEN, Instituto Universitario de Oncología del Principado de Asturias (IUOPA), Universidad de Oviedo, C/Julián Clavería 7, Facultad de Medicina, Oviedo 33006, Spain.
| | - Raquel Alvarez-Alonso
- Research Group BITTEN, Instituto Universitario de Oncología del Principado de Asturias (IUOPA), Universidad de Oviedo, C/Julián Clavería 7, Facultad de Medicina, Oviedo 33006, Spain.
| | - Saúl Redondo
- Research Group BITTEN, Instituto Universitario de Oncología del Principado de Asturias (IUOPA), Universidad de Oviedo, C/Julián Clavería 7, Facultad de Medicina, Oviedo 33006, Spain.
| | - Juan Carvajal
- Research Group BITTEN, Instituto Universitario de Oncología del Principado de Asturias (IUOPA), Universidad de Oviedo, C/Julián Clavería 7, Facultad de Medicina, Oviedo 33006, Spain.
| | - Germán Villamizar
- Research Group BITTEN, Instituto Universitario de Oncología del Principado de Asturias (IUOPA), Universidad de Oviedo, C/Julián Clavería 7, Facultad de Medicina, Oviedo 33006, Spain.
| | - Claudio J Villar
- Research Group BITTEN, Instituto Universitario de Oncología del Principado de Asturias (IUOPA), Universidad de Oviedo, C/Julián Clavería 7, Facultad de Medicina, Oviedo 33006, Spain.
| | - Felipe Lombó
- Research Group BITTEN, Instituto Universitario de Oncología del Principado de Asturias (IUOPA), Universidad de Oviedo, C/Julián Clavería 7, Facultad de Medicina, Oviedo 33006, Spain.
| |
Collapse
|
64
|
Du Y, Wang Y, Huang T, Tao M, Deng Z, Lin S. Identification and characterization of the biosynthetic gene cluster of polyoxypeptin A, a potent apoptosis inducer. BMC Microbiol 2014; 14:30. [PMID: 24506891 PMCID: PMC3943440 DOI: 10.1186/1471-2180-14-30] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Accepted: 02/04/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Polyoxypeptin A was isolated from a culture broth of Streptomyces sp. MK498-98 F14, which has a potent apoptosis-inducing activity towards human pancreatic carcinoma AsPC-1 cells. Structurally, polyoxypeptin A is composed of a C₁₅ acyl side chain and a nineteen-membered cyclodepsipeptide core that consists of six unusual nonproteinogenic amino acid residues (N-hydroxyvaline, 3-hydroxy-3-methylproline, 5-hydroxypiperazic acid, N-hydroxyalanine, piperazic acid, and 3-hydroxyleucine) at high oxidation states. RESULTS A gene cluster containing 37 open reading frames (ORFs) has been sequenced and analyzed for the biosynthesis of polyoxypeptin A. We constructed 12 specific gene inactivation mutants, most of which abolished the production of polyoxypeptin A and only ΔplyM mutant accumulated a dehydroxylated analogue polyoxypeptin B. Based on bioinformatics analysis and genetic data, we proposed the biosynthetic pathway of polyoxypeptin A and biosynthetic models of six unusual amino acid building blocks and a PKS extender unit. CONCLUSIONS The identified gene cluster and proposed pathway for the biosynthesis of polyoxypeptin A will pave a way to understand the biosynthetic mechanism of the azinothricin family natural products and provide opportunities to apply combinatorial biosynthesis strategy to create more useful compounds.
Collapse
Affiliation(s)
| | | | | | | | | | - Shuangjun Lin
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China.
| |
Collapse
|
65
|
Cai G, Napolitano JG, McAlpine JB, Wang Y, Jaki BU, Suh JW, Yang SH, Lee IA, Franzblau SG, Pauli GF, Cho S. Hytramycins V and I, anti-Mycobacterium tuberculosis hexapeptides from a Streptomyces hygroscopicus strain. JOURNAL OF NATURAL PRODUCTS 2013; 76:2009-2018. [PMID: 24224794 DOI: 10.1021/np400145u] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Thirty-five thousand actinomycete extracts were screened for anti-Mycobacterium tuberculosis (M. tb) activity, followed by C18 cartridge fractionation of 37 prioritized extracts. Based on MICs against replicating and nonreplicating M. tb, and IC50 values against Vero cells to generate selectivity indices, seven fractions from seven different strains were selected for further examination. When cultured in G.S.S. media and extracted with ethyl acetate, the Streptomyces hygroscopicus strain ECUM 14046 yielded an extract with promising anti-M. tb activity and a well-defined chromatographic profile. Fractionation by preparative HPLC and subsequent structure elucidation of two active fractions using 1D- and 2D-NMR and MS methods revealed the presence of two cyclohexapeptides, hytramycins V and I, each containing three unusual piperazic acid moieties. The use of (1)H iterative full spin analysis (HiFSA) on both hytramycins confirmed that quantum mechanics-simulated spectra match the experimental data, and all J(H,H) and δH values are consistent with the proposed structures. The absolute configuration of each amino acid moiety was determined by Marfey's method. The MICs against replicating and, more importantly, nonreplicating M. tb fall into the range of some existing second-line anti-TB drugs, such as streptomycin and capreomycin, respectively. The activities were maintained against M. tb strains that represent the major global clades, as well as H37Rv-isogenic strains that are resistant to individual clinical anti-TB drugs.
Collapse
Affiliation(s)
- Geping Cai
- Institute for Tuberculosis Research and ‡Department of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, University of Illinois at Chicago , Chicago, Illinois 60612, United States
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
66
|
Chen Y, Lu Y, Zou Q, Chen H, Ma D. A Scalable Process to the Key Intermediate of Cilazapril, (S)-1-Benzyloxycarbonylhexahydropyridazine-3-carboxylic Acid, Through a Novel Cascade Course. Org Process Res Dev 2013. [DOI: 10.1021/op400155u] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Yu Chen
- Shanghai AoBo Bio-pharmaceutical Technology Co., Ltd., No. 1011, Halei Road, Zhangjiang High-Tech
Park, Shanghai 201203, P.R. China
| | - Yuwei Lu
- Shanghai AoBo Bio-pharmaceutical Technology Co., Ltd., No. 1011, Halei Road, Zhangjiang High-Tech
Park, Shanghai 201203, P.R. China
| | - Qing Zou
- Shanghai AoBo Bio-pharmaceutical Technology Co., Ltd., No. 1011, Halei Road, Zhangjiang High-Tech
Park, Shanghai 201203, P.R. China
| | - Huansheng Chen
- Shanghai AoBo Bio-pharmaceutical Technology Co., Ltd., No. 1011, Halei Road, Zhangjiang High-Tech
Park, Shanghai 201203, P.R. China
| | - Dawei Ma
- Shanghai AoBo Bio-pharmaceutical Technology Co., Ltd., No. 1011, Halei Road, Zhangjiang High-Tech
Park, Shanghai 201203, P.R. China
| |
Collapse
|
67
|
Beveridge RE, Batey RA. Total synthesis of the cytotoxic enehydrazide natural products hydrazidomycins A and B by a carbazate addition/Peterson olefination approach. Org Lett 2013; 15:3086-9. [PMID: 23734814 DOI: 10.1021/ol401275f] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The first total syntheses of two natural antitumor enehydrazide compounds (hydrazidomycins A and B) and a related positional isomer of hydrazidomycin B (elaiomycin B) have been accomplished in a rapid and stereocontrolled fashion using a Peterson elimination approach. A regioselective silyl epoxide ring opening reaction with Boc-carbazate followed by base-mediated Peterson siloxide elimination stereospecifically installed the key Z-enehydrazide functionality. The use of Boc-carbazate allowed for the differential functionalization of the hydrazide nitrogens.
Collapse
Affiliation(s)
- Ramsay E Beveridge
- Davenport Research Laboratories, Department of Chemistry, University of Toronto , 80 St. George Street, Toronto ON, Canada
| | | |
Collapse
|
68
|
Blair LM, Sperry J. Natural products containing a nitrogen-nitrogen bond. JOURNAL OF NATURAL PRODUCTS 2013; 76:794-812. [PMID: 23577871 DOI: 10.1021/np400124n] [Citation(s) in RCA: 253] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
As of early 2013, over 200 natural products are known to contain a nitrogen-nitrogen (N-N) bond. This report categorizes these compounds by structural class and details their isolation and biological activity.
Collapse
Affiliation(s)
- Lachlan M Blair
- School of Chemical Sciences, University of Auckland, 23 Symonds Street, Auckland, New Zealand
| | | |
Collapse
|
69
|
Zhang H, Chen J, Wang H, Xie Y, Ju J, Yan Y, Zhang H. Structural analysis of HmtT and HmtN involved in the tailoring steps of himastatin biosynthesis. FEBS Lett 2013; 587:1675-80. [PMID: 23611984 DOI: 10.1016/j.febslet.2013.04.013] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2012] [Revised: 04/03/2013] [Accepted: 04/08/2013] [Indexed: 11/26/2022]
Abstract
Himastatin is a novel antibiotic featuring a bicyclohexadepsipeptide structure. On the himastatin biosynthesis pathway, three cytochrome P450s (HmtT, HmtN, HmtS) are responsible for the post-tailoring of the cyclohexadepsipeptide backbone. Here we report the crystal structures of HmtT and HmtN. The overall structures of these two proteins are homologous to other cytochrome P450s. However, the exceptionally long F-G loop in HmtT has a highly unusual conformation and extends deep into the active site. As a result, the F/G helices of HmtT are both kinked. In contrast, the F/G helices of HmtN are straight. Also, the F/G helices in HmtT and HmtN take distinctive orientations, which may be a contributing factor for the substrate specificity of these two enzymes.
Collapse
Affiliation(s)
- Huaidong Zhang
- Key Laboratory of Molecular Biophysics, Ministry of Education, Wuhan 430074, Hubei, China
| | | | | | | | | | | | | |
Collapse
|
70
|
Martínez-Muñoz A, Monge D, Martín-Zamora E, Marqués-López E, Álvarez E, Fernández R, Lassaletta JM. Asymmetric organocatalytic Strecker-type reactions of aliphatic N,N-dialkylhydrazones. Org Biomol Chem 2013; 11:8247-55. [DOI: 10.1039/c3ob41437j] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
71
|
Ji Z, Qiao G, Wei S, Fan L, Wu W. Isolation and Characterization of Two Novel Antibacterial Cyclic Hexapeptides from Streptomyces alboflavus 313. Chem Biodivers 2012; 9:1567-78. [DOI: 10.1002/cbdv.201100364] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
72
|
Neumann CS, Jiang W, Heemstra JR, Gontang EA, Kolter R, Walsh CT. Biosynthesis of piperazic acid via N5-hydroxy-ornithine in Kutzneria spp. 744. Chembiochem 2012; 13:972-6. [PMID: 22522643 DOI: 10.1002/cbic.201200054] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2012] [Indexed: 11/10/2022]
Abstract
Which came first? We have investigated the biosynthesis of the piperazic acid (Piz) building blocks in the kutzneride family of metabolites. The flavin-dependent oxygenase KtzI was shown to convert ornithine to N(5)-OH-Orn. LC-MS/MS showed (13)C(5)-labeled versions of these two amino acids to be direct precursors of piperazic acid in vivo.
Collapse
Affiliation(s)
- Christopher S Neumann
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 240 Longwood Avenue, Boston, MA 02115, USA
| | | | | | | | | | | |
Collapse
|