Contents

(C)         Organic Chemistry

Poster – C - 1

Acrylamide Derivatives as Antiallergic Agents. Synthesis and Structure-Activity Relationships of Piperazinyl- Amino acids-Acrylamide Derivatives.

A.M. Shalaby, O.I. Abd El-Salam and A. Kalmosh

National Research Centre, Dokki; Cairo-12622, Egypt

An interesting approach for the design of antiallergics is rationally considered. According to Nishikawa et al (1-3), new compounds were synthesized comprising acrylic acid and piprazine segments.

These compounds were structurally designed as 5- lipoxygenase antiallergic agents depending on two action mechanisms of the ready drugs used to treat allergy e. g. "Oxatomide", which contain piprazine moiety and "Transilate and Amoxamox", which contain aerylic acid segment. In harmony with these findings, our work is focused to synthesize analogous compounds in the hope to increase the activity of these compounds using amino acid conjugates, which have an important role activities and decrease side effects: to increase biological

References:

1-Y. Nishikawa, T. Shindo, K. Ishi, H. Nakamura, T. Kon and H. Uno, Chem. Pharm. Bull.. 37 (1), 100 (1989).

2-Y. Nishikawa; T. Shimoto; K. Ishii; H. Nakamura, T. Kon and H. Uno, J. Mod. Chem, 32 (3), (1989),

3-Y. Nishikawa; T, Shimoto; K. Ishii; H. Nakamura; T. Kon and H. Uno, Chew. Pharm, Bull, 37(3), 684-687 (1989).

Poster C - 2

Nitriles in Heterocyclic Synthesis: Synthesis of Pyrido [3’,2’,4:,5] thieno[2,3-d] pyrimidines Derivatives

A.M. Hussein, F.A. Abu-Shanab, E.A. Eshak, and
M.A. Abdel Rahim

Chem. Dept., Faculty of Science, Al-Azhar University, Assuit 71524, Egypt

6-amino-3,5-dicyano-4-methylpyridine-2(1H)-thione 1 reacted with a-haloketones to give the s-alkylated derivatives 2a-m.  Compound 2a-m undergoes cyclization into thieno[2,3-d]pyridine derivatives 3a-m upon treatment with ethanolic sodium ethoxide. Saponification of 3a gave the amino acid 4, which afforded 5 when refluxed in Ac₂O.  Treatment of 5 with NH₄OAc/AcOH gave 6a. Compound 6a also obtained when 3c were refluxed in Ac₂O. Reaction of 3a with formamide give 7 and with hydrazine hydrate gave 8.  The thiourea derivative 9 was obtained by reaction of 3a with benzoyl isothiocyanate.  Compound 9 when refluxed in alcoholic KOH gave 10 and with 98% H₂SO₄ gave 12.  Acetylation of 3a with Ac₂O gave the acetyl derivatives 13, which on treatment with aniline afforded 14. Compound 14 was cyclized with H₂SO₄ to 15. Finally treatment of compound 5 with aniline in AcOH afforded 6b.

Poster – C - 3

Studies with Polyfunctionally Substituted Heterocycles: Synthesis of Novel Pyrimidine Derivatives as Antimicrobial Agents

A.A. Aly and S.A. Nassar

Chemistry Department, Faculty of Science, Benha University, Benha, Egypt, E-mail:alymaboud@hotmail.com

A variety of pyrimidine derivatives (2-5) were synthesised via the reaction of (1) with formamide, urea, thiourea, phenyl isothiocyanate and carbon disulphide. Also the reaction of (1) with triethyl orthoformate was investigated to give (6). The latter reacted with some nitrogen nucleophile to afford newer pyrimidine derivatives (7,8). All the synthesized compounds were identified on the basis of elemental analyses and spectral data.

Poster – C -4

One-Pot Synthesis of Ellipticine Analogues as Potential Non-Nucleoside Reverse Transcriptase Inhibitor

A.A. Hamed

Chemistry Department, Faculty of Science, Minufiya University, Shebin El-Koom, Egypt

Ellipticine is naturally occurring alkaloid. The discovery of its anti-tumour activities, DNA interclation, as well as inhibition of reverse transcriptase has led to intensive synthetic, biological, and pharmacological studies. These interesting properties of ellipticine prompted us to develop a new generation of its analogues by simple route and good yield. For instance, p-tolylisocyanate (1) reacts with benzotrichloride in presence of SbCl₅   to furnish the isoindolium salt (2). According to Ritter Reaction, the chlorocarbenium ion (2) reacts with nitriles affording the corresponding nitrilium salt , which rearrange to the thermodynamically more stable 2-azoniaallene salt (3). Boiling 3 under reflux at 83C for few hours produce the polycyclic condensed ring 4 which regarded as ellipticine analogues.

Poster – C – 5

Uses of 2- Acetylbenzimidazole in the Synthesis of Some New Pyridine, Thienopyridine, Thia[1,5,7]triazafluorenone and Pyridopyrimidine

A.A. Hassanien^a, E.I. Ibrahim^b and M.E. Afifi^a

^a Chemistry Department, Faculty of Education, Suez Canal University, El-Arish, Egypt

^b Chemistry Department, Faculty of  Science, Suez Canal University, Egypt

Reaction of 2-acetylbenzimidazole with some arylaldehydes under different condition in variable molar ratios afforded the corresponding compounds 2-4 in acceptable yields. When compound 2 treated with various types of reagent compounds 5, 6, 7, 8, 14 and 15 were obtained. The structure of all new products was confirmed on the basis of their correct elemental analyses and compatible spectral data.

Poster – C - 6

Synthesis of 4-Spiro Substituted Cyclohexyl-5,6,7,8-Tetrahydro-1,3- Benzoxazine Derivatives and N-Substituted Benzamide Derivatives

S.S. Elmorsy, E.A. Abdel-Salam and E.M. Kandeel

Chemistry Department- Mansoura University, Mansoura, Egypt

The title compounds (R= H, 4-CH₃, 4-C(CH₃)₃, 2-C₆H₁₁) are synthesized efficiently under mild conditions in one pot reaction of different cycloclohexanone derivatives with benzonitrile in methylene chloride as solvent  in the presence of silicon tetrachloride and zinc chloride according to the following equation:

The chemical structures of 4-spiro substituted cyclohexyl-5,6,7,8-tetrahydro-1,3-benzoxazine derivatives and N- substituted benzamide derivatives are elucidated by I.R, H¹-N.M.R and M.S spectroscopic methods.

Poster – C - 7

A Facial Route for Conversion of Cycloalkylidene Malononitrile Derivatives into Amides and / or Esters

Doria S. Badawy and S.S. Elmorsy

Chemistry Department, Faculty of Science, Mansoura University, Mansoura, Egypt

It became necessary to prepare large quantities of functionalized cycloalkalidene malononitrile for organic synthesis. We report here that a very facile conversion of selectively cyanide group with the aid of tetrachlorosilane - alcohol in molar ratio.

The controlled conversion of cycloalkalidene malononitrile into amides or esters by combination of tetrachlorosilane and alcohol was found to depend on the reaction conditions as shown in the following equations.

Poster – C - 8

Synthesis of Some New Thiazolidin-5-one Derivatives of Pharmaceutical Interest

M.A. Metwally, Eman M. Keshk, A. Fekry and H.A. Etman

Chemistry Department, Faculty of Science, Mansoura University, Mansoura, Egypt

The title compound 2 was prepared by the reaction of diphenylthiourea 1 with chloroacetyl chloride. Compound 2 on treatment with phenyl isothiocyanate in basic medium afforded the non-isolable intermediate 3, which undergo cyclization on addition of chloroacetyl chloride to give 4. Compound 4 when coupled with diazotized anilines, afforded the corresponding arylazo derivatives 5. Also the reactions of compound 2 with a variety of reagents e.g. ninhydrin, aldehydes and aromatic aldehydes were investigated. The structures of these compounds were established by analytical and spectral data.

Poster – C - 9

Synthesis of 3,4-Biheterylthieno[2,3-b]thiophenes

Part I: Synthesis of 3,4-Bi(1^{`</sup>,3<sup>`},4^`-thiadiazolyl-, s-triazolyl-,

1^{`</sup>,3<sup>`},4^{`</sup>-thiadiazinyl-, 1<sup>`},3^{`</sup>,4<sup>`}-triazinyl-, 1^{`</sup>,3<sup>`}-thiazolyl-, 1^{`</sup>,3<sup>`}-thiazinyl- and primidinyl)thieno[2,3-b]thiophenes.

H.M. Moustafa, A. Khodairy and H. Abdel-Ghany

Chemistry Department, Faculty of Science, Sohag, Egypt

3,4-Diamino-2,5-dicarbethoxythieno[2,3-b]thiophene (1) was allowed to react with NaNO₂ and active methylenes to afford the corresponding azo compounds 2a-c. Hydrazonyl chloride 2a was treated with carbon disulfide, phenyl isothiocyanate, benzonitrile, benzyl cyanide, malononitrile, benzalaniline, ethyl mercaptoacetate and ethyl glycinate to give 1,3,4-thiadiazolyl-, s-triazolyl-, 1,3,4-thiadiazinyl-, 1,3,4-triazinylthieno[2,3-b]thiophenes 3-6, respectively. The reaction of 2b,c with urea, thiourea, and guanidine afforded pyrimidinyl- and thiazinylazothieno[2,3-b]thiophenes 7-10, respectively. Bithiazolylthieno[2,3-b]thiophenes 11 and 13 were synthesized by treating compound 1 with CS₂ along with halo compounds. The addition of S,S-, N,S- and N,O- acetals to the Schiff base 14 afforded compounds 15-17, respectively.

Poster – C - 10

New Azodisperse Dyes with Thiazole Ring for Dyeing Polyester Fabrics

A.M. Khalil, M.A. Metwally, E. Abdel-Latif, and F.A. Amer

Department of chemistry, Faculty of Science, Mansoura University, Mansoura, Egypt

Diazotized aryl amines were coupled with 2-aminothiazole derivatives to give 5-arylazo-2-aminothiazoles, which on reaction with different reagents such as acetic anhydride and benzoyl chloride yielded the corresponding 2-(N-acetylamino)-5-arylazothiazole and 2-(N-benzoyl-amino)-5-arylazothiazole derivatives. These dyes were applied to polyester as disperse dyes and their fastness properties were evaluated.

Poster – C - 11

Synthesis and Bilogical Evaluation of Some Fused Rings with 4-Amino-1, 2,4-triazine Derivative

M.A. El-Badawi, A.A. El-Barbary. Y.M. Loksha. and M. El-Daly¹

Chemistry Department, Faculty of Science, Tanta University, Tanta, Egypt

¹ Molecular Biology.Unit, National Liver Institute, Menoufia University, Shebin El-Kom, Egypt

Refluxing 4-amino-6-methyl-5-oxo-3-thioxo-2,3,4,5-tetrahydro-l,2,4-triazine (1) with 1 chloro-2,4-dinitrobenzene in DMF yielded 3-methyl-6-nitro-10H-benzo[l,2,4]thiadiazino[2,3-c][l,2,4]triazin-4-one (2). Condensation of (1) with 2,4-pentandione in refluxing acetic acid furnished 6-methyl-4-(l-methyl-3-oxobut-l-enylamino)-3-thioxo-3.4-dihydro-2H-[l,2,4]triazin-5-one (3). Refluxing (1) with 2-bromo-propionyl bromide in anhydrous benzene afforded the corresponding N-acetylated derivative (4) which was cyclized by treatment with triethylamine to give 3,8-Dimethyl- [1,2,4] triazino[3,4-A]-[l,3,4]thiadiazine-4,7-dione (5). Also, some triazinyl-quinazolinones (7a,b) were obtained by fusion of (1) with 6-bromo(and/or6,8-dibromo)-2-methyl-3,l-benzoxazin-4H-ones (6a,b). All of the new compounds prepared were tested against HBV.

Poster – C - 12

Novel utility of (4S, 5S) and (4R,5R)-4,5-dimethoxy-2-imidazolidinones: An Alternative Route for Synthesis of Chiral 4-Substituted 2-imidazolidinone Auxiliaries and vicinal Diamines

A.A.-M. Abdel-Aziz¹, Fatma Goda² and T. Kunieda³

Dept. of Medicinal Chemistry¹ and Dept. of Pharmaceutical Organic Chemistry², Faculty of Pharmacy, Mansoura University, Mansoura 35561, Egypt

Fac. of Pharm. Sci., Kumamoto Uni., 5-1 Oe-honmachi, Kumamoto 862-0973, Japan³

The vicinal diamine skeleton is a structural unit found in a substantial number of compounds of biological and medicinal interest, and functions as a chelating ligand for transition metals as well as main group metal complexes. Thus, the use of 1,2-diamines as reliable building blocks in organic synthesis has increased considerably, particularly in the field of catalytic asymmetric synthesis. Hence, a versatile route for the chiral synthesis of both unsymmetric and C₂-symmetric 1,2-diamines from simple, inexpensive starting materials would be highly desirable.

The simple heterocycle, 1,3-dihydro-2-imidazolone 1, which contains vicinal amino groups masked with a carbonyl group and an olefinic enamine moiety and which would be susceptible to various modes of addition reactions, suggests its synthetic potential as a building block for the preparation of 1,2-diamines. In this report we wish to report on a promising route for an efficient synthesis of optically active 1,2-diamines 5a,b and novel methodology for synthesis of chiral 4-(1-adamantyl) 4a and 4-tert-butyl-2-imidazolidinone 4b through the key intermediates, (4S,5S) and (4R,5R)-4,5-dimethoxy-2-imidazolidinones 2a,b, which are readily accessible from the 2-imidazolone 1. Both the 4- and 5-methoxy groups on the 2-imidazolidinones 2a,b either undergo a stepwise and regioselective substitution, which is fully stereocontrolled by a vicinal group with organo cuprates, followed by ring opening to give the 1,2- diamines 5a,b, as outlined in Scheme 1, or subjected to unusual regio-stereocontrolled reduction with steric bulky organo cuprates; 1-adamantyl or tert-butyl; resulting the chiral 5-methoxy-2-imidazolidinone 3. It should be noted that the 4-methoxy group is preferentially replaced with organo metals in the presence of Lewis acids, due to the higher stability of acyliminium cation intermediate, which is generated in situ. Compound 3 can easily be converted to our previously reported chiral 4-substituted 2-imidazolidinone auxiliaries 4a,b without loss of optical activity, as evidenced by spectrographic data.

Scheme 1

Poster – C - 13

Synthesis of Some Acyclonucleosides of Thieno[2,3-d]pyrimidines with Expected Antiviral Activity

F.M.E. Abdel Megeid, A.E. Rashad, and M.E. Zaki

Photochemistry Department, National Research Center, Dokki, Cairo

In continuous of our previous work in synthesis of thienopyrimidines as antiviral candidates, so the reaction of thiophene derivative (1) with triethyl orthoformate or triethyl orthoacetate gave compounds 2 and 3. Compounds 2 and 3 when treated with P₂S₅ in pyridine gave the corresponding pyrimidinethione derivatives 4 and 5. Compounds 4 and 5 were treated with chloroethyl methyl ether to give the corresponding acyclonucleosides 6 and 7, respectively. All structures were elucidated with spectral data [Ms, IR, ¹H NMR, ¹³C, and X-ray.

Poster – C - 14

A Facile One Pot Conversion of L-Aryl-4(H)-3,2-benzoxazin-4-one to 2-Aryl-4(H)-3,1-benzoxazin -4-one and Quinazolinone Derivatives

A.F. El-Kafrawy

Chemistry Department , Faculty of Science , Ain Shams University Abbassia , Cairo, Egypt

3,2-Benzoxazin -4-one(l) has been obtained from interaction of 2-carboxy-(2,5-dimethyl)benzophenone with hydroxylamine hydrochloride in pyridine. The interaction of the latter with anthranilic acid in boiling butanol afforded 3,1-benzoxazinone (2). Treatment of benzoxazinone derivative (2) with formamide gave 2-aryl- 4(3H) quinazolinone (3). The behaviour of compound (3) towards compounds containing active hydrogen e.g. phthalimide, a-naphthol, b-naphthol, morpholine and benzamide under Mannich reaction conditions afforded Mannich bases (7). Reaction of quinazolinone derivative (3) with PCl₅/POCl₃ yielded. Choroquinazoline (4). This chloroderivative undergoes cyclocondensation reaction when submitted to react with acylhydrazines namely, acetylhydrazine, benzoylhydrazine and salicyloyl hydrazine and gave the bridgehead nitrogen compounds (5). Also, compound (4) reacts with thiosemicarbazide to give thiocarbamoyl hydrazinoquinazoline (6) Compound (6) undergoes cyclocondensation when allowed to react with ethylchloroacetate and / or w-bromoacetophenone to give l-(thiazol-2-yl)-2-(quinazolin-4-yl) hydrazin derivatives (8) and (9), respectively.

Poster – C - 15

Synthesis and Biological Evaluation of Some New Spiro Indoline-Based Heterocycles

Eman M. Keshk, Sh.M. El-Bady, M.A. Hanna^a and
A.H. Abdel-Rahman

Department of Chemistry, Faculty of Science, Mansoura University, Mansoura, and ^aDemiatta, Egypt

Several new spiroindoline-based heterocycles were synthesized by preior preparation of 2-oxoindol-3-ylidene malononitrile and 2-oxoindol-3-ylidene-ethyl cyanoacetate and subsequent reaction of the latter arylidene derivatives with nitrogen-containing heterocycles. Reaction of the produced Michael adducts with hydrazine hydrate afforded the target compounds in an average good yield. Structure of these products was confirmed by elemental as well as spectral analyses. Encouraging results were obtained on testing and evaluation of the hitherto synthesized compounds for their herbicidal and fungicidal activities.

Poster – C - 16

A New Synthesis of Tetrazole Derivatives from Thioamides in Mild One-Step Method Using Tetrachlorosilane / Sodium Azide Reagent

S.S Elmorsy, A.A.S. El-Ahl, A.H. Elbeheery*, F. A. Amer

Chemistry Department. Mansoura University, Mansoura, Egypt

* Chemistry Department, U.A.E. University. Al-Ain, U.A.E

A new, rather simple method for the conversion of thioamides and similar structures into tetrazole derivatives is described. The procedure employs TCS /NaN₃ in acetonitrile as a solvent under ambient or reflux conditions and leads to high yields. The structure of tetrazole derivatives obtained are elucidated by I.R., H¹- NMR, UV and MS spectroscopic methods. Such compounds are of increasing interest for their pharmaceutical properties.

Poster – C - 17

Synthesis and Reactivity of Some Pyridazine Derivatives

A.M. Kamal El-Dean

Chemistry Department, Faculty of Science, Assiut University, Assiut 71516, Egypt, E-mail: a.eldean@aun.eun.eg

In continuation of our program[1-3] in the synthesis and reactivity studies of some pyridazine derivatives herein we report the synthesis of some pyridazine derivatives. Ethyl 3-phenyl-1,6-dihydro-6-oxo-pyridazine-5-carboxylate 1 was reacted with amino compounds to give the corresponding, substituted carboamides 2a-d. The carbohydrazide 2a, was reacted with aromatic aldehydes, carbon disulfide, nitrous acid, acetyl acetone and phenyl isothiocyanate to produce compounds 3-7. The thiourea derivative 7 was cyclized in alkaline medium to afford mercaptotriazolyl derivative 8. Both the oxadizolyl and triazolyl derivatives 4 and 7 were underwent S-alkylation to give the corresponding S-alkyl derivative 9, 10 respectively. Carboazide 5 underwent Curtius rearrangement, while it reacts with alcohols, amines to give corresponding carbamates 11 and urea derivatives 12. Also, when it heated in dry xylene, the oxazolopyridazine 13 was obtained.

[1]      Sh. M. Radwan and A. M. Kamal El-Dean; Pharmazie; 52, 483 (1997).

[2]      A. M. Kamal El-Dean, A. A. Geies and Sh. M. Radwan, Bull. of the Polish Academy Science; 47, 135 (2) 831 (1999).

[3] Sh. M. Radwan and A.M. Kamal El-Dean; Phosphorus, Sulfur and Silicon; 164, 299 (2000).

Poster – C - 18

Synthesis of Coumarins and Furocoumarins in Solvent-Free Conditions

A. Shockravi^a, H. Valizadeh^a and M.M. Heravi^b

^aDepartment of Chemistry, School of Sciences, Teacher Training University, Tehran, Iran

^bDepartment of Chemistry, School of Sciences, Azzahra University, Vanak, Tehran, Iran

1- Synthesis of coumarins via the Bechmann and Kneovenagel reactions, in Solventless System under Microwave Irradiation¹.

2- Microwave Assisted of the Bechmann Reaction on ZnCl­₂ / Al₂O₃ to the Synthesis of Furocoumarins and Regioselective Bromination of furocoumarins in Solvent-free Conditions².

3- One-Pot and Facile Synthsis of Simple Coumarins via the Wittig Reaction Under Microwave Irradiation in Solventless System.

1) A. Shockravi, H. Valizadeh, M.M. Heravi,; Phosphorus Sulfur and Silicon, (2002), in press.

2) A. Shockravi, H. Sharghi, H. Valizadeh, M.M. Heravi, Indian J. Heterocycl. Chem., (2002),11, 331.

Poster – C - 19

Novel Synthesis of 1-(1,2,4-Triazolo[1,5-a]pyridinon-2-yl) Substituted Polyols

A.A. Ismail, S. El-Kousy and M. EI-Ghonamy

Chemistry Department, Faculty of Science, Menufia University, Shebin El-Koom, Egypt

New route for the synthesis of l-(l,2,4-triazols[l,5-a]pyridinon-2-yl) substituted polyols. 2 Cyanoacetohydroazide 1 was reacted with aldehydro-sugar 2 to give the corresponding hydrazones 3a-d in good yields. The synthesized hydrazones 3a-d were reacted with benzylidene malononitrile 4 via Michael addition to afford 1-(1,2,4- triazolo[l,5-a]pyridinon-2-yl)substituted polyols 7a-d.

Poster – C - 20

Synthesis and Reactions of New Indolyl-1,3,4-Oxadiazole, Triazole and Pyrazole Derivatives of Potential Pharmaceutical Interest.

A.A.H. Farghaly

Chemistry Department, Faculty of Science, Assiut University, Assiut 71516, Egypt, E-mail: elrahman2001@hotmail.com

The key intermediate 1 was prepared by the reaction of the indole-3-carboxylic ester with hydrazine hydrate. Treatment of the hydrazide with CDI in refluxing dioxane afforded the oxadiazolone compound 2 (X = O, Y = O), where as its reaction with CS₂ in dry pyridine gave the oxadiazolthione derivative 2 (X = S, Y= O). The interaction of the hydrazide with phenylisocynate furnished the corresponding compound 3. Compound 2 (X = S, Y = O) was allowed to react with hydrazine hydrate to give the corresponding triazolo compound 2 (X = S, Y = NHNH₂). Cyclization of the compound 3 with alcoholic KOH furnished the triazolo compound 2 (X = S, Y = NPh). Reaction of 2 with chloroacetone and phenacyl bromide gave the corresponding compound 4. These compounds expected to be of potential pharmaceutical interest.

Poster – C - 21

Synthesis and Reactions of Some Fused Oxazinone, Pyrimidinone, Thiopyrimidinone and Triazinone Derivatives as Antianalgesic, Anticonvulsant and Antiparkinsonisn

A.E. Amr^a, M.I. Hegab^b and A.A. Ibrahiem^a

^a Organic Chemistry Department, ^b Photochemistry Department, National Research Center, Dokki, Cairo, Egypt.

A series of the fused thiophene ring with pyridine, pyrimidinone, oxazinone and Triazinone derivatives 3-6, were synthesized by reacting of 2,6-bis[3'-amino-4'-aryl-2'-substituted-thieno[2,3"b]pyridin-6'-yl] pyridine I as starting materials 2 with different reagents. The pharmacological screening of the new compounds showed a good antianalgesic, anticonvulsant and antiparkinsonisn activities.

Poster – C - 22

Synthesis of Nitrogen Heterocyclic Compounds Containing Benzo[i]homochromanone of Potential Anticancer Activity

A.G. Hammam and Naglaa A. Abd El-Hafez

Applied Organic Chemistry Department, National Research Centre, Dokki, Cairo, Egypt

In our previous work and through our cooperation with N.C.I (U.S.A) in the drug discovery program, we have found that heterocyclic compounds containing nitrogen atom and fused to other heterocyclic ring possess anticancer activity.

References:

1-   Hammam, A.G.; Abd El-Hafez, N.A.; Midura, W.H. and Mikolajczk, M. Z.Naturforch, 55b, 417 (2000).

2-   Hammam, A.G.; Sharaf, M. A. and Abd El-Hafez, N.A,  Indian J. Chem., 40B, 213 (2001).

Poster – C - 23

Synthesis of 4-(3-Anilino-3-thienomethylpyrazol-t-yl)quinolme Derivatives and Related Di(tri)cyclic Systems

A.A. Hassanien^a, M.E.A. Zaki^b and O.A. Fathalla^b

^aDepartment of Chemistry, Faculty of Education, Suez Canal University, El-Arish and ^bNational Research Center, Dokki, Cairo Egypt

Interaction of la,b with ortho esters furnished 2a-d. Compounds 2a,b reacted with hydrazine hydrate to afford N-aminoimino derivatives 3a,b. which considered as good precursors to synthesis pyrazolotriazolo-pyrimidine derivatives. The structure of all synthesized compounds were confirmed by elemental analysis and spectral data.

Poster – C - 24

Reactivity of Substituted Chloramines in Raschig Synthesis

M. Elkhatiba,b, C. Durichea, C. Darwicha, F. Elomarb, H. Delalua

a Laboratoire Hydrazines et Procιdιs, FRE CNRS 2397, Universitι Claude Bernard Lyon 1, Bβtiment 731 (Berthollet), 3^θme ιtage, 43 boulevard du 11 novembre 1918, F-69622 Villeurbanne Cedex, France.

b Laboratoire de Chimie Appliquιe, Universitι Libanaise, Facultι des Sciences, Section 3, BP 826, Tripoli, Liban. {mazen@ul.edu.lb}

The unsymmetrical hydrazines are used in the pharmaceutical industry as precursors of medicinal drugs. Apart the nitrosamine process, currently abandoned for their toxicological properties, the Raschig method constitutes a more environmentally sound route for industrial preparation of hydrazines. It involves the two following reactions:

NH3 (or NH4+)  +  HOCl (or OCl-)NH2Cl  +  H2O

(1)        NH2Cl  +  RR’NH  +  OH-RR’NNH2  +  H2O  +  Cl-

However, it presents the disadvantage to take to numerous by-products. In particular, a parallel reaction to (1) leads to a substituted chloramine of which the quantity increases as pH decreases and becomes preponderant at pH 8. The mechanism involves either the ionized form of amine or chloramine:

(2)        NH2Cl  +  RR’NH2+RR’NCl  +  NH4+

or   NH3Cl+  +  RR’NHRR’NCl  +  NH4+

RR’NCl is unstable and decomposes according to pH leading to different products. In neutral or acidic medium, the substituted chloramine acts as a halogenating agent and leads to corresponding amine. In alkaline medium, it undergoes a dehydrohalogenation with the formation of imine:

 + OH- + H2O + Cl-

Depending on the nature of substituents, the imines are likely to hydrolyze or precipitate in polymeric form:

  +  H2O  +  RNH2

n  solid polymer

The industrial preparation of hydrazines undertakes at pH ≥ 12.5. In these conditions, the imines are the major products of the decomposition of substituted chloramines. To avoid any precipitation, sodium borohydride was used to reduce RR’NCl before its conversion into imine:

(3)        BH4-  +  2 RR’NCl2 RR’NH  +  BH2Cl2-

The principal results of the kinetics of formation of substituted chloramines and their reduction by sodium borohydride will be discussed. To elucidate the reaction mechanism, the study has been extended to various chloramines (R and R’ are hydrogen, aliphatic, alicyclic, aromatic and semi-aromatic group). The activation parameters have been also determined.

Poster – C - 25

Attempted Conversion of 3,5-Diphenyl-2(3H)-furanone into Other Heterocycles

Ahmed I. Hashem

Chemistry Department, Faculty of Science, Ain Shams University. Abbassia 11566, Cairo

Abnormally, 3,5-diphenyl-2(3H)-furanone II, obtained by ring closure of a-phenyl-b-benzoylpropionic acid I, reacts with semicarbazide without ring opening but with isomerization to the corresponding 2(5H)-furanone IV. However, it was possible to obtain the semicarbazide derivative III by the reaction of the acid chloride V with Semicarbazide. Ring closure of the semicarbazide III is dependent on the reaction conditions. Thus in acid medium the pyridazinone VI was obtained, but in alkaline medium the triazole VII was the only reaction product. The structures of the products were confirmed from their elemental analyses and spectroscopic properties.

Poster – C - 26

Dithioacetalization and Azathioacetalization of Cyanoketene Acetals under Phase Transfer Catalysis (PTC) Conditions.

A.M.M. El-Saghier

South Valley University, Faculty of Science, Department of Chemistry, Sohag, Egypt, E-mail: el saghier@yahoo.com

The synthesis of ketene S,S-acetals 1a,b or ketene N,S-acetals 2a,b by reaction of either malononitrile or acetylacetone along with carbon disulfide or phenyl isothiocyanate in 1:1 molar ratio using solid-liquid phase transfer catalysis conditions [dioxane/K₂CO₃/tetrabutyl ammonium bromide (TBAB)]. Ketene S,S-acetals 1a,b or ketene N,S-acetals 2a,b reacts in situ with a variety of ylidenemalononitriles to afford the desired spiro[l,3]dithiin heterocycles 3a,b, 4a,b, 5a-d, 6a-d, 7a-d and 8a,b or Spiro[l,3]thiazine heterocycles.

Poster – C - 27

Synthesis and Utility of N-[4-(N-substituted sulfamoyl)phenyl] cyanothioformamidtes in the Synthesis of Heterocyclic Compounds

A.M.S. El-Shareif^*, M.S.A. El-Gaby, A.A. AtaIla and A.A. El-Adasy

*Chemistry Dept, Faculty of Science, Al-Azhar University Nasr City, Cairo, Egypt

Chemistry Dept., Faculty of Science, Al-Azhar Assiut University, Assiut 71524, Egypt

The novel cyanothioformamides (2a-d) were prepared by treatment of isothiocyanato-sulfonamides (la-d) with potassium cyanide at room temperature. Cyclocondensation of ompounds (2) with phenyl isocyanate as electrophile furnished the corresponding imidazolidines (3). The reactivity of compounds (3) towards some nitrogen nucleophiles was investigated. Thus. the thiosemicarbazone (4) and imidazo[4.5-b]quinoxaline (5) were synthesized by condensation of compounds (3) with thiosemicarbazide and o-phenylenediamine, respectively. Treatment of (3) with hydrochloric acid afforded compound (6). Our investigation was extended to include the reactivity of cyanothioformamide (2) towards o-aminophenol, anthranilic acid and o-phenylene-diamine and yielded the corresponding heterocycles (7), (8) and (9) derivatives. Structures of the synthesized compounds were established by their elemental analysis and spectral data. The evaluation of the antimicrobial activity of some new synthesized compounds was carried out.

Poster – C - 28

A Novel Stereoselective Synthesis of Enantiomerically Pure (+)-Codonopsinine via O-(2-Pyrrolidinon-5-yl)trichloro-acetimidates as Amidoalkylating Agents

Ahmed O. H. El-Nezhawy

National Research Centre, Chemistry of Natural and Microbial Products Department, Dokki, Cairo, Egypt. E-mail, nzhawy7@yahoo.com

(+)-Codonopsinine[(+)-1], the enantiomer of natural (-)-Codonopsinine^1,2 was synthesized in enantiomerically pure form from L-tartrate, which furnishe with trichloroacetonitrile O-(2-pyrrolidinon-5-yl)tricloroacetimidate 2. α-Amidoalkylation studies of 2 with the electron rich benzene derivative as C-nucleophile afforded 5-C-aryl-2-pyrrolidinone 3. Target Compound (+)-1 was readily obtained from 3 via Grignard addition to the homochiral lactam elaborated through lewis-acid induced deoxygenation.

References

1- Matkhalikova, S. F.; Malikov, V. M.; Yunusov, S. Yu. Khim. Prir. Soedin 1969, 5, 607.

2- Matkhalikova, S. F.; Malikov, V. M.; Yunusov, S. Yu. Khim. Prir. Soedin 1969, 5, 30.

Poster – C - 29

Einstein Coefficients and Mean Electronic Transition Moment of Some Organic Molecules at Low Temperature

Ali A.K. Hussain

College of Science, University of Baghdad, Jadiriah, Baghdad, Iraq

Some organic molecules (ethylbenzene and bromobenzene) were examined using matrix isolation technique (MI). This new technique is used for trapping isolated molecule of the species of interest in a large excess of an inert material by rapid condensation at a low temperature, so that, the diluent forms a rigid matrix. MI requires approximately an ideal environment for isolating the molecule under investigation in order to approach the gas phase environment. A complete description of Ml system and its benefits are presented. Several parameters such as, Einstein A and B coefficients, and mean electronic transition moment of the mentioned molecules have been measured at 18 K. Higher transition moment values were obtained for ethylbenzene molecule (1.04x10⁶ and 0.68xl0⁸) in CO and AT matrices respectively relative to that of bromobenzene molecule.

Poster – C - 30

Synthesis, Antibacterial and Antifungal Activity of 1,2-Bis(2-thioxo-5-alkyl-1,3,5-thiadiazin-3-yl) ethane-1-carboxylic Acid and its Related Analogues.

A.M. Abdelal¹, S.A.A. El-Bialy¹, A. EI-Shorbagy² and
S.M.M. Kheira³

¹Departments of Pharmaceutical Organic Chemistry, ²Microbiology Faculty of Pharmacy, University of Mansoura, Mansoura -35516 Egypt

³Faculty of Pharmacy, Assiut University, Assiut, Egypt

In a search for promising antibacterial and/or antifungal compounds, eight new 1,2-bis(2-thioxo-5-alkyl-1,3,5-thiadiazin-3-yl)ethane-1-carboxylic acid (1) were synthesized by the reaction of ethyl 2,3-diaminopropionate, carbon disulfide, formaldehyde, and the appropriate alkyl amine. In addition, eight new N, N-dimethyl-1, 2-bis(2-thioxo-5-alkyl-1,3,5-thiadiazin-3-yl)ethane-1-carboxamides (H) were synthesized by the reaction of (I) with POCI₃ and diethylamine. Structural elucidation is based on elemental analysis, IR and ¹HNMR. The newly prepared compounds were screened for their in-vitro antibacterial activity against certain strains of pathogenic bacteria..Moreover, The title compounds were tested for their antifungalactivity in-vitro against pathogenic, phytopathogenic and aflatoxin producing fungi. The results revealed that some of these compounds have significant activity as potential antibacterial and antifungal agents. These compounds exhibited varied inhibitory effects on growth or sporutation of some tested fungal species.

Poster – C - 31

One Pot Synthesis of Pyrido[1,2-H]pyrimidines and 3-[Aryldiazenyl] pyrazolo[1,5-a]pyrimidines: Reaction of 2-Aryl-3,3-bis(methylthio)-acrylonitriles with Heterocyclic Amines

A.M. Hussein^* and M.A. Mohamed

*Chemistry Department, Faculty of Science, Cairo University, Beni-Suef Branch, Beni-Suef, Egypt

Textile Department, Industrial Education College, Ministry of Higher Education, Beni-Suef. Egypt

The reaction of ketene dithioacetals 1 with 2-aminopyrazoles and 2-aminopyridine was established to afford the interesting 3-[aryldiazenyl]-pyrazolo[l/5-fl]pyrimidine 6 and pyrido[l/2-a]pyrimidine derivatives 5 respectively. The synthesized compounds were expected to posses a potential biological activities as analogues of purine base.