Essential Oils of Some Saudi Pulicaria and Artemisia species
H. Z. Alkhathlan, M. Al-Zoman, R. M. Basha, A. A. Mousa and H. M. G. Al-Hazimi Oriental J. Chem., 1991, 7, 204
Abstract
The constituents of the essential oils of two Pulicaria species are reported here for the first time. In addition, the oils of a Pulicaria and five Artemisia species have been analyzed and compared with previous studies.
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بالاشتراك في البحث
Application of Phosphorus, Arsenic and Antimony Reagents in the Synthesis of Heterocyclic Compounds
Hamad Z. Alkhathlan and Hamed A. Al-Lohedan
Phosphorus, Sulfur and Silicon, 1991, 61, 367
Abstract
The ability of different reagents of the type R3XBr2 where R are various alkyl, alkoxide, phenyl and phenoxide groups and X is P, As and Sb to promote an intramolecular cyclization of suitably substituted aromatic diamines has been investigated. The type of R group and X was found to have a great influence on the ability of these reagents to promote this type of cyclization. Best results were obtained when R= OMe and
X= P.
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مساعد باحث عند الدكتور حمد بن زيد الخثلان
Studies on the Staudinger Reaction
Hamad Z. Alkhathlan
Oriental J. Chem., 1992, 6, 50
Abstract
Different reagents of the type R3X (where R= various groups, X= P, As, Sb) were tested in their ability to promote an intramolecular aza-Wittig reaction. These reagents were reacted with a suitable azide and the yields of the cyclized products were calculated.
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مساعد باحث عند الدكتور حمد بن زيد الخثلان
Synthesis and Spectroscopic Studies of Novel Quinoline Derivatives
Hamad Z. Alkhathlan
Synth. Commun., 1992, 22, 2659
Abstract
An intramolecular Wittig reaction of some substituted aminoacetophenones was used for the synthesis of novel quinoline derivatives. In addition, the base induced cyclization of the aminoacetophenones was investigated. The IR and NMR spectra of the quinoline derivatives are reported.
مساعد باحث عند الدكتور حمد بن زيد الخثلان ___________________________________________________
Novel Approach to Pyrrolo[1,2-a]quinoline-1,5-diones
Hamad Z. Alkhathlan
J. Chem. Res., 1992, (S) 260, (M) 1984
Abstract
The condensation of 2-aminoacetophenone with acid anhydrides is investigated. Different fused 4-quinolones derivatives were prepared in one step via this condensation. In addition, different N-substituted imides were also obtained.
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Sesquiterpene Lactones from Artemisia Species
Hamad Z. Alkhathlan, A. A. Mousa and H. M. G. Al-Hazimi
J. Chem. Soc. Pak., 1992, 14, 151
Abstract
Naturally occurring sesquiterpene lactones from Artemisia species which appeared in the literature during the last six years (1984-1989) have been reviewed.
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مساعد باحث عند الدكتور حمد بن زيد الخثلان
Chemistry of Various Pulicaria Species
Hassan M.G. Al-Hazimi and Hamad Z. Alkhathlan
J. Chem. Soc. Pak., 1992, 14, 233
Abstract
Secondary metabolites from various Pulicaria species up to the end of 1990 have been reviewed.
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مساعد باحث عند الدكتور حمد بن زيد الخثلان
A New Diterpene and Flavonoids from Pulicaria somalensis
Hassan M. G. Al-Hazimi and Hamad Z. Alkhathlan
J. King Saud Univ. (Science), 1993, 5, 141
Abstract
A new diterpene of clerodane type and three known methylated flavones (chrysosplenol D, chrysoplenetin and casticin) have been isolated from the aerial parts of Pulicaria somalensis and characterized by spectroscopic methods. chrysoplenetin and casticin have been isolated from the Pulicaria genus for the fires time.
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مساعد باحث عند الدكتور حمد بن زيد الخثلان
Spectroscopic Studies of Benzimidazole, Quinoxaline and Quinoline Derivatives
Hamad Z. Alkhathlan and Hamed A. Al-Lohedan
J. Chem. Res., 1995, (S) 10, (M) 201
Abstract
Four fused benzimidazoles, two quinoxalines and two fused quinoline derivatives were studied with respect to their mass, NMR and IR spectra; the compounds were chosen in order to compare the effect of the size of the hetero ring and the presence of C=N and C=O on their spectral behaviour.
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مساعد باحث عند الدكتور حمد بن زيد الخثلان
Naturally Occuring Non-Alkaloidal Phenanthrenes
Hassan M.G. Al-Hazimi and Hamad Z. Alkhathlan
J. Saudi Chem. Soc., 1997, 1, 47
Abstract
In this review, an attempt has been made to list all new non-alkaloidal phenanthrenoids which have isolated from the different plant families. The antimicrobial activities of those compounds is included.
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مساعد باحث عند الدكتور حمد بن زيد الخثلان
Stilbenes and Bibenzyls in Higher Plants
Hassan M.G. Al-Hazimi and Hamad Z. Alkhathlan
J. King Saud Univ. (Science), 1997, 9, 161
Abstract
Stilbenes and their dihydroderivatives, bibenzyls, which have been isolated from higher plants up to the end of 1994 are reviewed.
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مساعد باحث عند الدكتور حمد بن زيد الخثلان
Chemical Constituents of T. aurilactum, R. vesicarius, P. orientalis, P. somalensis and A. abyssinica Grown in Saudi Arabia
Hamad Z. Alkhathlan and Hassan M.G. Al-Hazimi
J. Chem. Soc. Pak, 1996, 18, 309
Abstract
The volatile oils of five plants, Tripleurospermum aurilactum, Rumex vesicarius, Pulicaria orientalis, P. somalensis and Artemisia abysinica were collected using steam distillation and their constituents were analyzed bu GS/MS. The first two plants are being studied for the first time. In addition, a further study on the chemical constituents of the third one is reported.
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مساعد باحث عند الدكتور حمد بن زيد الخثلان
Naturally Occuring Iridoids During the Period 1990-1993
.Hassan M.G. Al-Hazimi and Hamad Z. Alkhathlan
J. Chem. Soc. Pak, 1996, 18, 336
Abstract
New iridoids, secoiridoids, bis-iridoids and other miscellaneous iridoids isolated during the period 1990-1993, together with their botanical sources are listed. Furthermore, the re-isolated iridoids during the period covered by the present review are also given.
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مساعد باحث عند الدكتور حمد بن زيد الخثلان
An Approach Towards Fused Thieno[3,2-b]pyridines
Hamad Z. Alkhathlan
Heterocycles, 1997, 45, 45
Abstract
A series of fused thieno[3,2-b]pyridines was prepared via the condensation of substituted 2-acetyl-3-aminothiophenes and acid anhydrides. In addition, selected examples of these compounds were prepared via an intramolecular Wittig reaction.
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Chemical Investigation on the Leaves of Hibiscus furcatus
T. K. Bindu, A. Saidutty, H. Z. Alkhathlan and P. M. Shafi
Asian J. of Chem., 1997, 9, 734
Abstract
The petroleum ether (60-80°C) extract of the leaves of Hibiscus furcatus yielded five components. They were identified to be friedelin, ß-sitosterol, taraxerol, a mixture of
n-alkanes in the C30-C34 range and a mixture of n-alkanols in the C28-C34 range by chemical and physical methods.
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مساعد باحث عند الدكتور حمد بن زيد الخثلان
Synthesis of 2,3-Disubstituted 4-Oxoquinolines and 3-Substituted Fused 4-Oxoquinolines
Hamad Z. Alkhathlan and Khalid A. Al-Farhan
Heterocycles, 1998, 48, 641
Abstract
Seven 2,3-disubstituted 4-oxoquinolines were prepared via two methods. In the first one 2,3-disubstituted 4-oxoquinolines were prepared via the condensation of 2-amino-œ-cyanoacetophenone with substituted phthalic anhydrides, while in the second method the fused isoindolo[2,1-a]quinolines and pyrolo[1,2-a]quinoline were first prepared and then converted to 4-oxoquinolines. X-ray crystal structure analysis of ethyl 2-[3-cyano-4-oxo-2-quinolyl]benzoate is reported.
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Radical Copolymerization and Characterization of N-(tri-n-butyltin)Maleimide Monomer with Styrene, Methacrylate and N-vinyl-2-pyrrolidinone
Nayef S. Al-Muaikel, Salem S. Al-Diab and Hamad Z. Alkhathlan
Asian J. of Chem., 1999, 11, 1259
Abstract
Three types of novel organotin polymers from polymerization of new organotin monomer N-(tri-n-butyltin)maleimide with styrene, methylmethacrylate and N-vinyl-2-pyrrolidinone in bulk at 65°C. Using 2,2-azo-bis-isobutyronitrile (AIBN) as initiator. Characterization of of the prepared copolymers was accomplished by IR, 1H-NMR spectra and elemental analysis. All the copolymers dissolved readily at room temperature in most polar aprotic solvents. The thermal stability of the polymers was evaluated by TGA and DSC measurements.
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Synthesis of New Di-(tri-n-butyltin)citraconate and its Copolymer
Nayef S. Al-Muaikel, Salem S. Al-Diab and Hamad Z. Alkhathlan
J. King Saud Univ. (Science), 2000, 12, 25
Abstract
Anew monomer of Di(tri-n-butyltin)citraconate has been synthesized by the reaction of citraconic anhydride and bis(tri-n-butyltin)oxide. This monomer was copolymerized with styrene using 2,2-azo-bis-isobutyronitrile (AIBN) as a free radical initiator. The monomer and copolymer were identified by elemental analysis, IR and NMR spectroscopy.
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Synthesis and Characterization of Novel Organotin Monomer of N-(tri-n-butyltin)Maleimide, Homopolymerization and Copolymerization with Styrene
Nayef S. Al-Muaikel, Salem S. Al-Diab , Hamad Z. Alkhathlan and Ahmed Al-Obied
J. Saudi Chem. Soc., 2000, 4, 43
Abstract
New monomer, N-(tri-n-butyltin)maleimide N-(TBTM) wes prepared by the reaction of maleimide (MI) with tri-n-butyltinoxide (TBTO) in the presence of acetone as a solvent. The prepared monomer was copolymerized with styrene (ST) using benzene as solvent with 1 mol.% of 2,2-azo-bis-isobutyronitrile (AIBN) as free radical initiator. The structure of new monomer, homopolymer and copolymer have been characterized by elemental analysis, IR and NMR, the molecular weights of the homopolymer and copolymer have been established by GPC.
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مساعد باحث عند الدكتور حمد بن زيد الخثلان
Naurally Occuring Pterocarpanoids and Related Compounds
H. M.G. Al-Hazimi and Hamad Z. Alkhathlan
J. King Saud Univ. (Science), 2000, 12, 93
Abstract
In the present review an effort has been made to list all pterocarpanoids and coumestans which have been isolated from various plants belonging to the plant family Leguminosae (Fabaceae) up to mid-1998. The antimicrobial activities as well as the biosynthesis pathways of the compounds are briefly included.
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مساعد باحث عند الدكتور حمد بن زيد الخثلان
Condensation Products of 3-Aminothiophenes with Acid Anhydrides
Hamad Z. Alkhathlan
Asian J. Chem., 2002, 14, 1427
Abstract
Condensation of substituted 3-aminothiophenes with six different carboxylic acid anhydrides resulted in the formation of three types of products: N-(substituted thienyl)imides, substituted carboxylic acids and fused thieno[3,2-b]pyridines. The IR, NMR and MS spectra of these compounds are discussed.
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Synthesis and X-ray crystal Structures of Novel Spiro 1,3-Benzoxazine Dimers
H. Z. Alkhathlan, M. A. Al-Saad, H. M. Al-Hazimi, K. A. Al-Farhan and
A. A. Mousa
J. Chem. Res. 2002, (S) 473, (M) 1023
Abstract
Novel spiro 1,3-benzoxazine dimmers are obtained when hydrazones of
2-hydroxyacetophenone are treated with triphosgene. An X-ray crystal structure and the NMR and MS spectra of these new compounds are reported and discussed.
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Quinazoline, Pyrazolo[1,5-c]quinazoline and Spiro Quinazoline Dimers from the Reaction of 2-Aminoacetophenene Hydrazones with Triphosgene
H. Z. Alkhathlan, M. A. Al-Saad, A. A. Mousa
H. M. Al-Hazimi, K. A. Al-Farhan and
J. Chem. Res. 2002, (S) 587, (M) 1201
Abstract
The reaction of hydrazones of 2-aminoacetophenone with triphosgene in dichloromethane or benzene in the presence of triethylamine gave quinazolines, pyrazolo[1,5-c]quinazoline and spiro quinazoline dimmers. The latter compounds are being reported for the first time. In addition, a 4,4-disubstituted quinazoline derivative is prepared and its X-ray crystal structure is reported.
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مساعد باحث عند الدكتور حمد بن زيد الخثلان
Synthesis of 4-alkoxy-4-methyl- and 4-alkoxy-4-fluoromethyl-1,3-benzoxazinones
Hamad Z. Alkhathlan
Tetrahedron, 2003, 59, 8163
Abstract
Cyclization of 2-hydroxyacetophenone hydrazones with triphosgene resulted in the formation of 4-methylene-1,3-benzoxazinones. These compounds were converted to 4-alkoxy-4-methyl-1,3-benzoxazinones and 4-fluoromethyl-4-methyl-1,3-benzoxazinones upon treatment with alcohols under refluxing conditions and F-TEDA-BF4 in acetonitrile and methanol, respectively.
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مساعد باحث عند الدكتور حمد بن زيد الخثلان
A One-Pot Synthesis of 1,3-Benzoxazines
Hamad Z. Alkhathlan
Synth. Commun., 2004, 34, 71
Abstract
Reaction of substituted 2-hydroxyacetophenones with amines under microwave irradiation (MW) gave the corresponding imines (Schiff bases) which were treated without separation or identification with triphosgene to give 4-methylene-1,3-benzoxazines in good yields.
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Synthesis, Spectroscopic Studies and X-Ray Crystal Structure of
N-Heteryliminophosphoranes
H. Z. Alkhathlan, M. A. Al-Jaradah, K. A. Al-Farhan and A. A. Mousa
Phosphorus, Sulfur and Silicon, 2004, 179, 1
Abstract
N-[2-(œ-Bromoacetyl)phenyl]imides (prepared in two steps from 2-aminoacetophenone) gave upon treatment with sodium azide fused azidoquinolines via an intamolecular cyclization. Reaction of the above azides with phosphines gave N-heteryliminophosphoranes. The IR, 1H-, 13C-, and 31P-NMR and MS spectra of these compounds as well as the X-ray crystal structure of two of them is reported.
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Three 2-(2-Phenylethyl)chromones and Two Terpenes from Agarwood
H. Z. Alkhathlan, H. M. Al-Hazimi, F. S. Al-Dhalaan and A. A. Mousa
Natural Product Research, 2005, 19, 367
Abstract
A new chromone, 7,8-dimethoxy-2-[2-(3'-acetoxyphenyl)ethyl]chromone (1) was isolated from an acetone extract of the Cambodian agarwood along with two known chromones, 6-methoxy-2-(2-phenylethyl)chromone (2) and 6,7-dimethoxy-2-(2-phenylethyl)chromone (3). In addition, an abietane ester (4) and the sesquiterpene dehydrofukinone (5) were isolated from the agarwood oil of the same origin. Structural elucidation of all isolated compounds was made on IR, 1H-, and 13C-NMR spectroscopic data.
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Essential Oils of A. Factorovskyi, K. Linearis, C. Arvensis, P. Babylonica, P. Cyanocarpa, L. Nucicaulis and R. Epapposum
S. A. Al-Mazroa, L. H. Al-Wahaibi, A. A. Mousa and H. Z. Alkhathlan
J. Saudi Chem. Soc., 2005, 9, 693
Abstract
The constituents of the essential oils of A. factorovskyi, K. linearis, C. arvensis, P. babylonica, P. cyanocarpa, L. nudicaulis and R. epapposum, all belonging to the family Compositae, are reported. The majority of these plants are studied herein for the first time. |
