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1.
Int J Mol Sci ; 13(2): 2148-2159, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22408444

RESUMO

Liquid-liquid iron(III) extraction was investigated using benzyl fatty hydroxamic acids (BFHAs) and methyl fatty hydroxamic acids (MFHAs) as chelating agents through the formation of iron(III) methyl fatty hydroxamate (Fe-MFHs) or iron(III) benzyl fatty hydroxamate (Fe-BFHs) in the organic phase. The results obtained under optimized conditions, showed that the chelating agents in hexane extract iron(III) at pH 1.9 were realized effectively with a high percentage of extraction (97.2% and 98.1% for MFHAs and BFHAs, respectively). The presence of a large amount of Mg(II), Ni(II), Al(III), Mn(II) and Co(II) ions did affect the iron(III) extraction. Finally stripping studies for recovering iron(III) from organic phase (Fe-MFHs or Fe-BFHs dissolved in hexane) were carried out at various concentrations of HCl, HNO(3) and H(2)SO(4). The results showed that the desired acid for recovery of iron(III) was 5 M HCl and quantitative recovery of iron(III) was achieved from Fe(III)-MFHs and Fe(III)-BFHs solutions in hexane containing 5 mg/L of Fe(III).


Assuntos
Compostos de Benzil/química , Ácidos Hidroxâmicos/química , Quelantes de Ferro/química , Ferro/isolamento & purificação , Extração Líquido-Líquido/métodos , Óleos de Plantas/química , Alcanos/química , Clorofórmio/química , Compostos Férricos/química , Heptanos/química , Hexanos/química , Concentração de Íons de Hidrogênio , Íons , Óleo de Palmeira , Xilenos/química
2.
J Oleo Sci ; 61(4): 189-95, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22450120

RESUMO

Fatty hydroxamic acids derivatives based on palm kernel oil which are phenyl fatty hydroxamic acids (PFHAs), methyl fatty hydroxamic acids (MFHAs), isopropyl fatty hydroxamic acids (IPFHAs) and benzyl fatty hydroxamic acids (BFHAs) were applied as chelating agent for copper liquid-liquid extraction. The extraction of copper from aqueous solution by MFHAs, PFHAs, BFHAs or IPFHAs were carried out in hexane as an organic phase through the formation of copper methyl fatty hydroxamate (Cu-MFHs), copper phenyl fatty hydroxamate (Cu-PFHs), copper benzyl fatty hydroxamate (Cu-BFHs) and copper isopropyl fatty hydroxamate (Cu-IPFHs). The results showed that the fatty hydroxamic acid derivatives could extract copper at pH 6.2 effectively with high percentage of extraction (the percentages of copper extraction by MFHAs, PFHAs, IPFHs and BFHAs were found to be 99.3, 87.5, 82.3 and 90.2%, respectively). The extracted copper could be quantitatively stripped back into sulphuric acid (3M) aqueous solution. The obtained results showed that the copper recovery percentages from Cu-MFHs, Cu-PFHs, Cu-BFHs and Cu-IPFHs are 99.1, 99.4, 99.6 and 99.9 respectively. The copper extraction was not affected by the presence of a large amount of Mg (II), Ni (II), Al (III), Mn (II) and Co (II) ions in the aqueous solution.


Assuntos
Cobre/química , Ácidos Graxos/química , Ácidos Hidroxâmicos/química , Óleos de Plantas/química , Cobre/isolamento & purificação , Ácidos Graxos/síntese química , Ácidos Hidroxâmicos/síntese química , Óleo de Palmeira
3.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 10): o2607-8, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-22064829

RESUMO

THE TITLE COMPOUND [SYSTEMATIC NAME: 5,10-di-hy-droxy-2,2-di-methyl-12-(2-methyl-but-3-en-2-yl)-pyrano[3,2-b]xanthen-6(2H)-one], C(23)H(22)O(5), isolated from the stem bark of Calophyllum soulattri, consists of four six-membered rings and a 2-methyl-but-3-en-2-yl side chain. The tricyclic xanthone ring system is almost planar [maximum deviation = 0.093 (2) Å], whereas the pyran-oid ring is in a distorted boat conformation. The 2-methyl-but-3-en-2-yl side chain is in a synperiplanar conformation. There are two intra-molecular O-H⋯O hydrogen bonds. In the crystal, mol-ecules are linked by C-H⋯O inter-actions, forming a zigzag chain propagating in [010].

4.
J Oleo Sci ; 60(6): 281-6, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21606615

RESUMO

Phenyl fatty hydroxamic acids (PFHAs) were synthesized from canola or palm oils and phenyl hydroxylamine (FHA) catalyzed by Lipozyme TL IM or RM IM. The reaction was carried out by shaking the reaction mixture at 120 rpm. The optimization was carried out by changing the reaction parameters, namely; temperature, organic solvent, amount and kind of enzyme, period of reaction and the mol ratio of reactants. The highest conversion was obtained when the reaction was carried out under the following conditions: temperature, 39°C; solvent, petroleum ether; kind and amount of lipase, 80 mg Lipozyme TL IM/mmol oil; reaction period, 72 h and FHA-oil ratio, 7.3 mmol FHA/ mmol oil. The highest conversion percentage of phenyl hydroxylaminolysis of the Ladan and Kristal brands commercial canola oils, palm stearin and palm kernel oils were 55.6, 52.2, 51.4 and 49.7 %, respectively.


Assuntos
Biocatálise , Ácidos Graxos Monoinsaturados/metabolismo , Ácidos Graxos/biossíntese , Ácidos Hidroxâmicos/metabolismo , Lipase/metabolismo , Óleos de Plantas/metabolismo , Ácidos Graxos/química , Ácidos Graxos Monoinsaturados/química , Ácidos Hidroxâmicos/química , Estrutura Molecular , Óleo de Palmeira , Óleos de Plantas/química , Óleo de Brassica napus
5.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 3): o612, 2011 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-21522369

RESUMO

In the title compound, C(13)H(19)NO(2), the dihedral angle between the benzene ring and the plane throught the non-H atoms of the amide group is 29.3 (1)°. The benzene ring and the alkane carbon skeleton plane are twisted slightly with respect to each other [5.40 (5)°]. In the crystal, mol-ecules are oriented with the amide groups head-to-head, forming N-H⋯O hydrogen-bonded dimers. The dimers are connected by further N-H⋯O hydrogen bonds into a ladder-like motif along the b axis.

6.
Molecules ; 16(8): 6634-44, 2011 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-25134767

RESUMO

Fatty hydroxamic acid derivatives were synthesized using Lipozyme TL IM catalyst at biphasic medium as the palm kernel oil was dissolved in hexane and hydroxylamine derivatives were dissolved in water: (1) N-methyl fatty hydroxamic acids (MFHAs); (2) N-isopropyl fatty hydroxamic acids (IPFHAs) and (3) N-benzyl fatty hydroxamic acids (BFHAs) were synthesized by reaction of palm kernel oil and N-methyl hydroxylamine (N-MHA), N-isopropyl hydroxylamine (N-IPHA) and N-benzyl hydroxylamine (N-BHA), respectively. Finally, after separation the products were characterized by color testing, elemental analysis, FT-IR and 1H-NMR spectroscopy. For achieving the highest conversion percentage of product the optimum molar ratio of reactants was obtained by changing the ratio of reactants while other reaction parameters were kept constant. For synthesis of MFHAs the optimum mol ratio of N-MHA/palm kernel oil = 6/1 and the highest conversion was 77.8%, for synthesis of IPFHAs the optimum mol ratio of N-IPHA/palm kernel oil = 7/1 and the highest conversion was 65.4% and for synthesis of BFHAs the optimum mol ratio of N-BHA/palm kernel oil = 7/1 and the highest conversion was 61.7%.


Assuntos
Ácidos Graxos/síntese química , Ácidos Hidroxâmicos/síntese química , Lipase/metabolismo , Óleos de Plantas/química , Elementos Químicos , Óleo de Palmeira , Espectroscopia de Prótons por Ressonância Magnética , Espectroscopia de Infravermelho com Transformada de Fourier
7.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 11): o3000, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22220018

RESUMO

In the title compound, C(19)H(29)NO, the C-C and C-N bond distances of the benzonitrile group are 1.445 (2) and 1.157 (2) Å, respectively. The aliphatic fragment adopts a bent zigzag arangement which differs from the planar zigzag arrangement normally observed in n-alkanes or long-chain alkyl-benzenes. In the crystal, inversion dimers linked by pairs of C-H⋯O hydrogen bonds occur. A C-H⋯N inter-action also occurs. In the crystal, mol-ecules are packed with the nitrile and aliphatic groups oriented in a head-to-tail fashion involving, forming a ripple-like motif along the a axis.

8.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 9): o2469, 2010 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-21588787

RESUMO

The triazole ring in the title compound, C(14)H(12)N(4)O(2)·H(2)O, makes dihedral angles of 36.9 (1) and 37.3 (1)° with the two benzene rings. Each hy-droxy group is a hydrogen-bond donor to a two-coordinate N atom of an adjacent mol-ecule; these O-H⋯N hydrogen bonds generate a layer parallel to the ab plane. Adjacent layers are linked by N--H⋯O and O(water)-H⋯O hydrogen bonds into a three-dimensional network.

9.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 12): o3331-2, 2010 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-21589606

RESUMO

The title compound, Artonol B, C(24)H(20)O(7), isolated from the stem bark of Artocarpus kemando, consists of four six-membered rings and one five-membered ring. The tricyclic xanthone ring system is almost planar [maximum deviation 0.115 (5) Å], whereas the pyran-oid ring is in a distorted boat conformation·The furan ring is almost coplanar with the fused aromatic ring, making a dihedral angle of 3.76 (9)°. The phenol ring serves as a intra-molecular hydrogen-bond donor to the adjacent carbonyl group and also acts as an inter-molecular hydrogen-bond acceptor for the methyl groups of adjacent mol-ecules, forming a three-dimensional network in the crystal.

10.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 12): o3362-3, 2010 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-21589631

RESUMO

The title compound (trivial name α-mangostin), C(24)H(26)O(6), isolated from Cratoxylum glaucum, is characterized by a xanthone skeleton of three fused six-membered rings and two 3-methyl-but-2-enyl side chains. The three rings in the structure are nearly coplanar, with an r.m.s. deviation for the tricyclic ring system of 0.0014 Å. The two 3-methyl-but-2-enyl side chains are in (+)-synclinal and (-)-anti-clinal conformations. Intra-molecular O-H⋯O and C-H⋯O inter-actions occur. The crystal structure is stabilized by inter-molecular O-H⋯O, C-H⋯O and C-H⋯π inter-actions.

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