Associate Professor Alison Ung

Hemtasin, C., Ung, A.T., Kanokmedhakul, S., Kanokmedhakul, K., Bishop, R., Sastraruji, T. & Bishop, D. 2012, 'Synthesis of alkaloid-like compounds via the bridging Ritter Reaction', Monatshefte f++r Chemie, vol. 143, no. 6, pp. 955-963.
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Alkaloid-like compounds containing a benzo[c]azepine core structure were successfully prepared in three steps from H-dibenzo[a,d]cyclohepten-5-ol via the bridging Ritter reaction. Biological studies of these compounds revealed that some of them are AChE inhibitors and antimalarial agents.

Sastraruji, K., Sastraruji, T., Ung, A.T., Griffith, R., Jatisatienr, A. & Pyne, S.G. 2012, 'Synthesis of stemofoline analogues as acetylcholinesterase inhibitors', Tetrahedron, vol. 68, no. 35, pp. 7103-7115.
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Thirty-two new stemofoline analogues were prepared from didehydrostemofoline for studies as AChE inhibitors. C-3 Side-chain modified amino, carbamate, triazole and oxazole stemofoline derivatives were prepared. In general the amine derivatives were found to be stronger inhibitors of AChE than their alcohol analogues that we previously reported. Compounds 5 and 26, with small C-3 side-chain substituents, were two of the most active inhibitors. Preliminary molecular docking studies suggested that these compounds may inhibit AChE by binding horizontally along the passage of the active-site gorge and block access to acetylcholine.

Sastraruji, T., Pyne, S.G. & Ung, A.T. 2012, 'Oxidation of acyclic alkenes and allyl and benzyl ethers with DIB/t-BuOOH/Mg(OAc)2', Tetrahedron, vol. 68, no. 2, pp. 598-602.
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Oxidation of (11Z)-1',2'-didehydrostemofoline with DIB/TBHP/Mg(OAc)(2)center dot 4H(2)O resulted in oxidative cleavage of the C-11-C-12 double bond instead of the desired allylic oxidation of the 1-butenyl side chain. Stemofoline gave a similar result. The oxidation of more simple terminal alkenes was regioselective and gave vinyl ketones while allyl and benzyl ethers gave acrylate and benzoate esters, respectively. Allyl and benzyl ethers could be chemoselectively oxidized in the presence of a terminal alkene or benzyl group. Oxidation of an internal alkene was poorly regioselective, in contrast to the oxidation of 1-substituted cyclohexenes.

Wang, Y., Su, D., Ung, A.T., Ahn, J. & Wang, G. 2012, 'Hollow CoFe(2)O(4) nanospheres as a high capacity anode material for lithium ion batteries', Nanotechnology, vol. 23, no. 5, p. art055402.
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Hollow structured CoFe(2)O(4) nanospheres were synthesized by a hydrothermal method. The uniform hollow nanosphere architecture of the as-prepared CoFe(2)O(4) has been confirmed by field emission scanning electron microscopy and transmission electron microscopy analysis, which give an outer diameter of 200-300 nm and a wall thickness of about 100 nm. CoFe(2)O(4) nanospheres exhibited a high reversible capacity of 1266 mA h g(-1) with an excellent capacity retention of 93.6% over 50 cycles and an improved rate capability. CoFe(2)O(4) could be a promising high capacity anode material for lithium ion batteries.

Sastraruji, T., Chaiyong, S., Jatisatienr, A., Pyne, S.G., Ung, A.T. & Lie, W. 2011, 'Phytochemical Studies on Stemona aphylla: Isolation of a New Stemofoline Alkaloid and Six New Stemofurans', Journal of Natural Products, vol. 74, no. 1, pp. 60-64.
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A new stemofoline alkaloid, (2'S)-hydroxy-(11S,12R)-dihydrostemofoline (3), new stemofurans M-R (8-13), and known compounds stemofoline (1), (2?S)-hydroxystemofoline (2), stemofuran E (4), stemofuran F (5), stemofuran J (6), and stilbostemin F (7) have been isolated from the root extracts of Stemona aphylla. The structures and relative configurations of these new compounds have been determined by spectroscopic data interpretation and from semisynthetic studies. These natural and semisynthetic alkaloids were tested for acetylcholinesterase inhibitory activities and were found to be 10-20 times less active than 1?,2?-didehydrostemofoline itself. Stemofurans 4, 6, 8, 11, and 13 were tested for their antibacterial and antifungal activities. Three of these showed antibacterial activities against MRSA with MIC values of 15.6 ?g/mL

Ung, A.T., Pyne, S.G., Joeffreys, G., Skelton, B.W. & White, A.H. 2011, 'Synthesis of 2-acetyl-5-(1,2,3,4,5,6-hexahydroxyhexyl) thiazoles', Monatshefte f++r Chemie - Chemical, vol. 142, no. 3, pp. 297-303.
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The syntheses of two diastereoisomers of 2-acetyl-5-(1,2,3,4,5,6-hexahydroxyhexyl) thiazole are reported. The synthesis of these diastereoisomers involved the coupling of 5-metallated 2-(1,1-dimethoxyethyl)thiazole with a Weinreb amide derived from d-gluconolactone, followed by asymmetric reduction of the ketone thus prepared. The stereochemistries and structures of some key compounds were determined by single-crystal X-ray structural analysis.

Chaiyong, S., Jatisatienr, A., Mungkornasawakul, P., Sastraruji, T., Pyne, S.G., Ung, A.T., Urathamakul, T. & Lie, W. 2010, 'Phytochemical Investigations of Stemona curtisii and Synthetic Studies on Stemocurtisine', Journal of Natural Products, vol. 73, no. 11, pp. 1833-1838.
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The isolation of two new Stemona alkaloids, 1-hydroxyprotostemonine and stemocurtisine N-oxide, and a new benzofuran, stemofuran L, from the root extracts of Stemona curtisii is reported. The major known alkaloids from this plant extract, stemocurtisine, stemocurtisinol, and oxyprotostemonine, were also isolated along with oxystemokerrine N-oxide. The nonalkaloid components of this extract included a new benzofuran derivative, stemofuran L, the known stemofurans F, J, and K, dihydro-+¦-tocopherol, and stigmasterol. Stemocurtisine and stemocurtisinol were converted to their respective N-oxides by oxidation. Stemocurtisine was converted to a tetracyclic derivative by oxidative cleavage of the +¦-butyrolactone ring, while stemocurtisinol gave a novel lactam derivative by oxidative cleavage of the C-4 side chain under basic conditions. The acetylcholinesterase inhibitory activities of some known and new alkaloids and their derivatives are also reported. All were 10-20 times less active as acetylcholinesterase inhibitors than the pyrrolo[1,2-a]azepine Stemona alkaloids stemofoline and 1Ô+¦,2Ô+¦-didehydrostemofoline. None of the stemofuran compounds showed significant antibacterial or antifungal activities.

Mbere-Nguyen, U., Ung, A.T. & Pyne, S.G. 2010, 'Synthesis of 2'-Aminoalkyl-1-benzylisoquinoline derivatives, medium sized ring analogues with mu opiod receptor binding activities', Tetrahedron, vol. 66, no. 23, pp. 4133-4143.
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Novel 20-aminoalkyl-1-benzylisoquinoline compounds and medium size ring analogues have been prepared using reductive alkylation methods. Four of these analogues were tested for biological activity across 48 different CNS receptors and were showed to have binding activities at the mu opiod receptor.

Sastraruji, K., Sastraruji, T., Pyne, S.G., Ung, A.T., Jatisatienr, A. & Lie, W. 2010, 'Semi-Synthesis and Acetylcholinesterase Inhibitory Activity of Stemofoline Alkaloids and Analogs', Journal of Natural Products, vol. 73, no. 5, pp. 935-941.
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Semisynthesis of the known Stemona alkaloids oxystemofoline (7) and methoxystemofoline (8) has been achieved starting from (11Z)-1Ô+¦,2Ô+¦-didehydrostemofoline (6), which confirmed their structures and absolute configurations. The synthesis of (1Ô+¦R)-...

Baird, M.C., Pyne, S.G., Ung, A.T., Lie, W., Sastraruji, T., Jatisatienr, A., Jatisatienr, C., Dheeranupattana, S., Lowlam, J. & Boonchalermkit, S. 2009, 'Semisynthesis and Biological Activity of Stemofoline Alkaloids', Journal of Natural Products, vol. 72, no. 4, pp. 679-684.
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The semisynthesis of the Stemona alkaloids (3?R)-stemofolenol (1), (3?S)-stemofolenol (2), methylstemofoline (3), and (3?S)-hydroxystemofoline (5) and the unnatural analogues (11E)-methylstemofoline (15) and 3?R-hydroxystemofoline (11) has been achieved starting from (11Z)-1?,2?-didehydrostemofoline (4). This synthesis allowed, for the first time, access to diastereomerically enriched samples of 1 and 2 and the assignment of their absolute configurations at C-3?. These compounds were obtained in sufficient quantities to allow for their biological testing. In a quantitative assay as AChE inhibitors, (11Z)-1?,2?-didehydrostemofoline (4) and (3?S)-hydroxystemofoline (5) were found to be the most active.

Batenburg-Nguyen, U., Ung, A.T. & Pyne, S.G. 2009, 'The synthesis of carbon linked bis-benzylisoquinolines using Mizoroki-Heck and Sonagashira coupling reactions', Tetrahedron, vol. 65, no. 1, pp. 318-327.
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Novel laudanosine dimers in which two laudanosine units are linked at C-2? via a two or three-carbon linker (alkane, alkene or alkyne) have been prepared using palladium-catalysed cross-coupling reactions (Mizoroki+Heck and Sonagashira reactions). In one example, a second three-carbon linker between the two isoquinoline N-atoms was also present leading to a novel macrocyclic ring system.

Mbere-Nguyen, U., Ung, A.T. & Pyne, S.G. 2009, 'The synthesis of carbon-linked bisbenzylisoquinolines via ruthenium- mediated olefin-metathesis', Tetrahedron, vol. 65, no. 31, pp. 5990-6000.
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Novel laudanosine dinners in which two laudanosine units are linked at C-2' via a two and four-carbon linker have been prepared using ruthenium-mediated olefin-metathesis. In addition, a second four-carbon linker between the two isoquinoline N-atoms was also present leading to a novel macrocyclic ring system. Five of these compounds showed higher cytostatic activity on three cancer cell lines than thalicarpine.

Mungkornasawakul, P., Pyne, S.G., Ung, A.T., Jatisatienr, A. & Willis, A. 2009, 'Stemofoline ethyl acetate solvate', Acta Crystallographica Section E-Structure Reports ..., vol. 65, no. 0, pp. O1878-U3157.
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Crystals of the title compound, C22H29NO5 center dot C4H8O2, {[systematic name: (2R,3R,5R,5aS,6R,8aR,9S)-(5Z)-5-[3-butyl-tetrahydro-6-methyl-2,5-methano-4,3,8a-[1]propanyl[3]ylidenefuro[3,2-f][1,4]oxazepin-7(5H)-ylidene]-4-methoxy-3-methylfuran-2(5H)-one ethyl acetate solvate} were isolated from the root extracts of Stemona aphylla (Stemonaceae). The structure closely resembles those of stemofoline derivatives which have previously been reported. Intermolecular contacts are observed between some C-bonded H atoms and nearby O atoms, perhaps indicating weak interactions which could influence the packing of species within the unit cell.

Mungkornasawakul, P., Chaiyong, S., Sastraruji, T., Jatisatienr, A., Jatisatienr, C., Pyne, S.G., Ung, A.T., Korth, J. & Lie, W. 2009, 'Alkaloids from the Roots of Stemona aphylla', Journal of Natural Products, vol. 72, no. 5, pp. 848-851.
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Three known compounds, stemofoline (1), (2'S)-hydroxystemofoline (2), and (11Z)-1',2'-didehydrostemofoline (3), along with two new alkaloids, stemaphylline (4) and stemaphylline-N-oxide (5), have been isolated from a root extract of Stemona aphylla. The structures of these alkaloids were determined on the basis of their spectroscopic data. The analysis of the crude dichloromethane extract by GC-MS in the EIMS mode showed the presence of alkaloids 1-4, the alkaloid 11, and stilbostemin R (12). The crude dichloromethane extract and 4 were tested for their comparative biological activities. The results of their acetylcholinesterase (AChE) inhibitory activities showed that the crude extract had higher activity than that of 4. The insecticidal properties of the crude extract and 4, using a topical application, showed that 4 had an activity similar to the positive control, methomyl, whereas the crude extract had much lower activity. Their antimicrobial activity against Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923, Pseudomonas auruginosa ATCC 27853, and Candida albicans ATCC 90028 was weak (MIC 62.5-125 ?g/mL, MBC 125-250 ?g/mL, MFC 125 ?g/mL) but much higher than that of the crude extract.

Sastraruji, K., Pyne, S.G., Ung, A.T., Mungkornasawakul, P., Lie, W. & Jatisatienr, A. 2009, 'Structural Revision of Stemoburkilline from an E-Alkene to a Z-Alkene', Journal of Natural Products, vol. 72, no. 2, pp. 316-318.
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Semisynthesis studies starting from (11Z)-1?,2?-didehydrostemofoline (4) indicated that the known Stemona alkaloid stemoburkilline is the Z-isomer and not the E-isomer as initially reported. The semisynthesis involved conversion of (11Z)-1?,2?-didehydrostemofoline (4) to 11(S),12(S)-dihydrostemofoline (3) followed by a stereoselective base-catalyzed ring-opening reaction to give (Z)-stemoburkilline (8). The same product was obtained using a similar synthetic protocol starting from isostemofoline (6) via a based-catalyzed ring-opening reaction of 11(S),12(R)-dihydrostemofoline (1). A re-examination of the crude root extracts of Stemona burkillii Prain and further NOE studies established stemoburkilline as the Z-isomer

Pyne, S.G., Ung, A.T., Jatisatienr, A. & Mungkornasawakul, P. 2007, 'The pyrido[1,2-a]azepine Stemona alkaloids', Maejo international journal of science and technology, vol. 1, no. 2, pp. 157-165.
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This paper reviews the isolation, structure elucidation, proposed biosynthesis and biological activities of the small, but increasing, number of pyrido[1,2-a]azepine Stemona alkaloids.

Taylor, S.R., Ung, A.T., Pyne, S.G., Skelton, B.W. & White, A.H. 2007, 'Intramolecular versus intermolecular oxidative couplings of ester tethered di-aryl ethers', Tetrahedron, vol. 63, no. 46, pp. 11377-11385.
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The oxidative cyclization of 3,4-dimethoxyphenyl 3,4-dimethoxyphenylacetate, through intramolecular biphenyl bond formation, was successful and gave the target seven-membered lactone in good yield (85+86%). All other ester substrates gave biphenyl products or their further oxidized products via intermolecular coupling of their radical cation intermediate with the neutral substrate. It appears that matching of the oxidation potentials and nucleophilicity of the two phenyl rings, the positioning of the ring substituents and the ease of E to Z isomerization about the ester C+O bond are important factors contributing to these product outcomes.

Taylor, S.R., Ung, A.T. & Pyne, S.G. 2007, 'Synthesis of benzo[c]chromen-6-ones via novel cyclic aryl-Pd(II)-ester enolate intermediates', Tetrahedron, vol. 63, no. 45, pp. 10889-10895.
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The examination of the palladium catalysed arylation reactions of mono-iodo derivatives of the phenyl and benzyl esters of benzoic acid, phenylacetic acid and dehydrocinnamic acid has resulted in the formation of benzo[c]chromen-6-ones, unexpected cinnamate and succinate products and diphenyl dimers. Many of these products can be rationalised as arising from novel cyclic ArPd(II)+enolate intermediates, formed by intramolecular C+H activation by ArPd(II).

Yong, S.R., Ung, A.T., Pyne, S.G., Skelton, B.W. & White, A.H. 2007, 'Syntheses of spiro[cyclopropane-1,3'-oxindole]-2-carboxylic acid and cyclopropa[c]quinoline-7b-carboxylic acid and their derivatives', Tetrahedron, vol. 63, no. 5, pp. 1191-1199.
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The synthesis of spiro[cyclopropane-1,3?-oxindole]-2-carboxylic acid, including novel 3-(2- and 3-pyridyl)-substituted analogues and the novel cyclopropa[c]quinoline-7b-carboxylic acid and their ester and amide derivatives is described. These syntheses involve diastereoselective cyclopropanation reactions of methyl 2-(2-nitrophenyl)acrylate and (3E)-(pyridin-2-ylmethylene)- and (3E)-(pyridin-3-ylmethylene)-1,3-dihydro-2H-indol-2-one with ethyl (dimethyl sulfuranylidene) acetate (EDSA). The synthesis of methyl cyclopropa[c]quinoline-7b-carboxylate involves a regioselective reductive cyclization of a nitro-diester precursor. The relative stereochemistry of key compounds has been determined by single-crystal X-ray structural analysis.

Yong, S.R., Ung, A.T., Pyne, S.G., Skelton, B.W. & White, A.H. 2007, 'Synthesis of novel 30-spirocyclic-oxindole derivatives and assessment of their cytostatic activities', Tetrahedron, vol. 63, no. 25, pp. 5579-5586.
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The synthesis of some novel 3?-spirocyclic-oxindole compounds, based on the spiro[indole-3,5?-isoxazolidin]-2(1H)-one, the 2?H-spiro[indole-3,6?-[1,3]oxazinane]-2,2?(1H)-dione and the 2?H-spiro[indoline-3,3?-pyrrolo[1,2-c][1,3?]oxazine]-1?,2(1H)-dione heterocyclic structures, is described. These compounds were prepared from methyl ?-(2-nitrophenyl)acrylate via [1,3]-dipolar cycloaddition reactions with two acyclic nitrones and one cyclic nitrone followed by reduction of the cycloadducts and then treatment with triphosgene. Two of these compounds showed significant cytostatic activity on three cancer cell lines with GI50 values of 2.6+4.1 ?M on the human breast cancer cell line, MCF-7.

Sastraruji, T., Jatisatienr, A., Issakul, K., Pyne, S.G., Ung, A.T., Lie, W. & Williams, M.C. 2006, 'Phytochemical Studies on Stemona Plants: Isolation of New Tuberostemonine and Stemofoline Alkaloids', Natural product communications, vol. 1, no. 10, pp. 813-818.
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Six new stemofoline alkaloids, (2`R)-hydroxystemofoline (5), (3`R)-stemofolenol (6), (3`S)-stemofolenol (7), 1`,2`-didehydrostemofoline-N-oxide (8), the first C19 stemofoline alkaloid, methylstemofoline (9), and the first glycosidated Stemona alkaloid, stemofolinoside (10), and three known alkaloids, (2`S)-hydroxystemofoline (2), (11Z)-1`,2`-didehydrostemofoline (3), and (11E)-1`,2`-didehydrostemofoline (4), have been isolated from a root extract of an unidentified Stemona species. The structure and relative configuration of these new alkaloids have been determined by spectral data interpretation and from semisynthetic studies.

Mungkornasawakul, P., Matthews, H., Ung, A.T., Pyne, S.G., Jatisatienr, A., Lie, W., Skelton, B.W. & White, A.H. 2005, 'Confirmation of the structure of oxystemokerrin by single crystal x-ray structural analysis and a proposed biosynthesis', A C G C Chemical Research Communications, vol. 19, pp. 30-33.
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Sastraruji, T., Jatisatienr, A., Pyne, S.G., Ung, A.T., Lie, W. & Williams, M.C. 2005, 'Phytochemical Studies on Stemona Plants: Isolation of Stemofoline Alkaloids', Journal of Natural Products, vol. 68, no. 12, pp. 1763-1767.
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Six new stemofoline alkaloids, (2óR)-hydroxystemofoline (5), (3óR)-stemofolenol (6), (3óS)-stemofolenol (7),1ó,2ó-didehydrostemofoline-N-oxide (8), the first C19 stemofoline alkaloid, methylstemofoline (9), and the first glycosidated Stemona alkaloid, stemofolinoside (10), and three known alkaloids, (2óS)-hydroxystemofoline (2), (11Z)-1ó,2ó-didehydrostemofoline (3), and (11E)-1ó,2ó-didehydrostemofoline (4), have been isolated from a root extract of an unidentified Stemona species. The structure and relative configuration of these new alkaloids have been determined by spectral data interpretation and from semisynthetic studies.

Ung, A.T., Pyne, S.G., Batenburg-Nguyen, U., Davis, A.S., Sherif, A., Bischoff, F. & Lesage, A.S. 2005, 'Synthesis and antagonist activities of 4-aryl-substituted conformationally restricted cyclopentenyl and cyclopentanyl-glutamate analogues', Tetrahedron, vol. 61, no. 7, pp. 1803-1812.
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The conformationally restricted glutamate analogues, 4-aryl-1-amino-2-cyclopentene-1,3-dicarboxylates and their cyclopentane analogues have been prepared in a diastereoselective manner. Biological studies of 12a and 12b indicates that both compounds are modest antagonists at mGluR2.

Yong, S.R., Williams, M.C., Pyne, S.G., Ung, A.T., Skelton, B.W., White, A.H. & Turner, P. 2005, 'Synthesis of 2-azaspiro[4.4]nonan-1-ones via phosphine-catalysed [3+2]-cycloadditions', Tetrahedron, vol. 61, no. 34, pp. 8120-8129.
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The phosphine-catalyzed [3+2]-cycloaddition of the 2-methylene ?-lactams 4 and 5 and the acrylate 6 with the ylides derived from the ethyl ester, the amide or the chiral camphor sultam derivative of 2-butynoic acid (7a+c) give directly, or indirectly after reductive cyclization, spiro-heterocyclic products. The acid 32 underwent Curtius rearrangement and then acid hydrolysis to give two novel spiro-cyclic ketones, 41 and 42.

Mungkornasawakul, P., Pyne, S.G., Jatisatienr, A., Supyen, D., Jatisatienr, C., Lie, W., Ung, A.T., Skelton, B.W. & White, A.H. 2004, 'Phytochemical and Larvicidal Studies on Stemona curtisii: Structure of a New Pyrido[1,2-a]azepine Stemona Alkaloid', Journal of Natural Products, vol. 67, no. 4, pp. 675-677.
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A new pentacyclic Stemona alkaloid, stemocurtisinol (3), with a pyrido[1,2-a]azepine A,B-ring system, and the known pyrrolo[1,2-a]azepine alkaloid oxyprotostemonine (4) have been isolated from a root extract of S. curtisii. The structure and relative stereochemistry of stemocurtisinol was determined by spectral data interpretation and X-ray crystallography. This compound is a diastereoisomer of oxystemokerrin and has the opposite configuration at C-4 and C-19. The individual alkaloid components showed significant larvicidal activity (IC50 4-39 ppm) on mosquito larvae (Anopheles minimus HO).

Mungkornasawakul, P., Pyne, S.G., Jatisatienr, A., Lie, W., Ung, A.T., Issakul, K., Sawatwanich, A., Supyen, D. & Jatisatienr, C. 2004, 'Phytochemical Studies on Stemona burkillii Prain: Two New Dihydrostemofoline Alkaloids', Journal of Natural Products, vol. 67, no. 10, pp. 1740-1743.
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Two new dihydrostemofoline alkaloids, 11(S),12(R)-dihydrostemofoline (3) and stemoburkilline (4), along with stemofoline (1) and 2`-hydroxystemofoline (2) have been isolated from a root extract of Stemona burkillii Prain. The structure and relative configuration of 3 have been determined via spectroscopic data and from comparison with synthetic 11(S),12(S)-dihydrostemofoline (5). The configuration of the exo-cyclic alkene group in 4 is tentively assigned as E on the basis of mechanistic considerations.

Mungkornasawakul, P., Pyne, S.G., Jatisatienr, A., Supyen, D., Lie, W., Ung, A.T., Skelton, B.W. & White, A.H. 2003, 'Stemocurtisine, the First Pyrido[1,2-a]azapine Stemona Alkaloid', Journal of Natural Products, vol. 66, no. 7, pp. 980-982.
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A new pentacyclic stemona alkaloid, stemocurtisine (2), with a novel pyrido[1,2-a]azapine A,B-ring system, has been isolated from a root extract of Stemona curtisii. The structure and relative stereochemistry was determined by spectral data interpretation and X-ray crystallography

Ung, A.T., Schafer, K., Lindsay, K.B., Pyne, S.G., Amornraksa, K., Wouters, R., Van der Linden, I., Biesmans, I., Lesage, A.S., Skelton, B.W. & White, A.H. 2002, 'Synthesis and Biological Activities of Conformationally Restricted Cyclopentenyl-Glutamate Analogues', Journal of Organic Chemistry, vol. 67, pp. 227-233.

Alshahateet, S.F., Bishop, R., Craig, D.C., Scudder, M.L. & Ung, A.T. 2001, 'Pseudopolymorphic Clathrate Structures Formed by an Alicyclic Dialcohol Inclusion Host1', Structural Chemistry, vol. 12, pp. 251-257.

Bishop, R., Craig, D.C., Dance, I.G., Scudder, M.L. & Ung, A.T. 1999, 'Interpenetrating inclusion lattices: comparison of the B-hydroquinone and ellipsoidal clathrate structures R', Journal of Structural Chemistry, vol. 40, no. 5, pp. 663-671.
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Crystallization of 2,7-dimethyltricyclo[43.1.13,8]undecane-syn-2,syn-7-diol 2 from acetonitrile or dichloro-methane yields the compounds (2)4-(guest) in space group 141/acd which are further examples of the ellipsoidal clathrate structure. Both enantiomers of 2 are linked through (O-H)4 cycles of hydrogen bonds to form a three-dimensional sublattice. Two inversion related sublattices interpenetrate thereby generating a superlattice with guest-occupied voids situated between the two individual sublattices. The two X-ray structures are compared and contrasted with that of Powell+s (hydroquinone)3 (SO2) clathrate compound.

Jeoffreys, G.R., Ung, A.T., Pyne, S.G., Skelton, B.W. & White, A.H. 1999, 'Synthesis of thiazole analogues of the immunosuppressive agent (1R,2S,3R)-2-acetyl-4(5)-(1,2,3,4-tetrahydroxybutyl)imidazole', Journal of the chemical chemistry. Perkin transactions 1, vol. 16, pp. 2281-2291.

Ung, A.T. & Pyne, S.G. 1998, 'Asymmetric synthesis of (1R,2S,3R)-2-acetyl-4- (1,2,3,4-tetrahydroxybutyl)thiazole', Tetrahedron-asymmetry, vol. 9, pp. 1395-1407.

Ung, A.T. & Pyne, S.G. 1998, 'Diastereoselective synthesis of (1S,2S,3R)- and (1R,2R,3R)-2-acetyl-5-(1,2,3,4-tetrahydroxybutyl)thiazole', Synlett, vol. 9, pp. 1395-1407.

Bishop, R., Craig, D.C., Dance, I., Gizachew, D., Scudder, M.L. & Ung, A.T. 1996, 'Helical tubulate inclusion compounds: size, shape, and stoichiometry', Molecular Crystals and Liquid crystals, vol. 278, pp. 65-76.

Ung, A.T., Pyne, S.G., Skelton, B.W. & White, A.H. 1996, 'Asymmetric Synthesis of (1R, 2S, 3R)-2-Acetyl-5-(1,2,3,4- tetrahydroxybutyi)thiazole', Tetrahedron, vol. 52, no. 44, pp. 14069-14078.
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A method for preparing the thiazole analogue 2 of the biologically active compound (1R, 2S, 3R)-2-acetyl-4(5)-(1,2,3,4-tetrahydroxybutyl)imidazole 1 is reported.

Ung, A.T. & Pyne, S.G. 1996, 'Synthesis Of Fluorescent And Biotinylated Analogues Of (Ir, 2s, 3r)-2.Acetyl-4(5)-(1,2,3,4-Tetrahydroxybutyl)Imidazole', Tetrahedron letters, vol. 37, no. 34, pp. 6209-6212.
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A method for preparing fluorescent and biotinylated analogues of the biologically active compound (1R, 2S, 3R)-2-acetyl-4(5)-(1,2,3,4-tetrahydroxybutyl)imidazole 1 is reported

Ung, A.T., Bishop, R., Craig, D.C., Dance, I., Gizachew, D. & Scudder, M.L. 1995, 'Structure and Analysis of Helical Tubulate Inclusion Compounds Formed by 2,6-Dimethylbicyclo[ 3.3.l]nonane-exo-2,exo-6-diol', Journal of the American Chemical Society, vol. 117, pp. 8745-8756.

Bishop, R., Craig, D.C., Dance, I., Scudder, M.L. & Ung, A.T. 1994, 'Helical tubuland diol-phenol co-crystals', Molecular Crystals and Liquid crystals, vol. 240, pp. 113-119.

Ung, A.T., Bishop, R., Craig, D.C., Dance, I. & Scudder, M.L. 1994, 'Formation and Structure of a New Family of Organic Cocrystals', Chemistry of Materials, vol. 6, pp. 1269-1281.

Bishop, R., Craig, D.C., Dance, I., Scudder, M.L. & Ung, A.T. 1993, 'Helical tubulate inclusion compounds', Supramolecular chemistry, vol. 2, pp. 123-131.

Ung, A.T., Bishop, R., Craig, D.C., Dance, I.G. & Scudder, M.L. 1993, 'Crystal engineering: helical tubuland diol-phenol co-crystrals', Journal of the Chemical Society, Chemical Communications, vol. 3, pp. 322-323.

Ung, A.T., Bishop, D.C., Craig, D.C., Dance, I.G. & Scudder, M.L. 1993, 'Helical tubulate inclusion compounds', Supramolecular chemistry, vol. 2, pp. 123-131.

Ung, A.T., Bishop, R., Craig, D.C., Dance, I. & Scudder, M.L. 1993, 'Helical Tubulate Inclusion Compounds of Ferrocene and Squalene', Journal of Inclusion Phenomena and Molecular Recognition in Chemistry, vol. 2, pp. 123-131.

Ung, A.T., Bishop, R., Craig, D.C., Dance, I. & Scudder, M.L. 1993, 'Prediction and Structure of Polymorphic Lattice Inclusion Compounds of 2,7-Dimethyltricyclo[4.3.1.03,8]undecanesyn- 2,syn-7-diol', Tetrahedron, vol. 3, no. 3, pp. 639-648.
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The host molecule 2,7-drmethylmcyclo[4 3 1 03~a]undecane-syn-2,rysyn-7-diol 1 is known to fotm two d&rent structural types of latuce mcluaon compound dependent on the guest molecule chosen Guests, mcludmg 1,Zdlchlorobenzene 2, have now been predicted which result in the formation of both lattice types according to the crystallisation conditions employed. Crvstal structures of the ellpsoidal clathrate type. (Racemic-1)4.( 1.2- chlorobenzene), space group I41/acd; and the helical tubulate hype `(Resolved-1)3 (1,2-Dichlorobenzene), space group P3121 are presented The latter polymorph 1s transformed into the former on heating in a sealed system

Bishop, R., Craig, D.C., Dance, I., Scudder, M.L. & Ung, A.T. 1992, 'Formation and stability of the helical tubuland diol inclusion lattice', Molecular Crystals and Liquid crystals, vol. 211, pp. 141-146.

Ung, A.T., Bishop, R., Craig, D.C., Dance, M.L. & Scudder, M.L. 1992, 'Crystal structures of helical tubulatr inclusion compounds formed by 2,6=dimethylbicyclo (3.3.1)nonane-exo-2, exo-6-diol', Royal Chemical Society. Journal. Perkin Transactions 2, vol. 6, pp. 861-862.

Ung, A.T., Bishop, R., Craig, D.C., Dance, I. & Scudder, M.L. 1992, 'Guest Control of Diol Inclusion Host Lattices', Structural Chemistry, vol. 3, pp. 59-61.

Ung, A.T., Bishop, R., Craig, D.C., Dance, I.G., Scudder, M.L. & Yunus, J. 1992, 'Ritter reactions. VII. ?Diverse reactivity of the 3-azatricycle[5.3.1.04,9]undec-2-ene system with dimethyl acetylenedicarboxylate', Australian Journal Of Chemistry, vol. 45, pp. 553-565.

Ung, A.T., Bishop, R., Craig, D.C., Dance, I. & Scudder, M.L. 1991, 'Stability of the helical tubuland inclusion lattice', Journal of the chemical society, vol. 15, pp. 1012-1014.

Ung, A.T., Bishop, R., Craig, D.C., Dance, I.G., Scudder, M.L. 1989, 'Ritter reactions. V. Further investigation of the 3-azatricyclo[5.3.1.04,9] under-2-ene system', Australian Journal Of Chemistry, vol. 42, pp. 1929-1937.