Synthesis of 1-[3-methyl-2(3H)-benzazolon-5- or 6-yl]-4-{4-[cis-2-(2,4-dichlorophenyl)-2-(1H-imidazol-1-yl-methyl)-1,3-dioxolan-4-yl]methyleneoxyphenyl}piperazines

Reactions of 3-methyl-6-[4-(4-hydroxyphenyl)-1-piperazinyl]-2(3H)-benzoxazolone, 3-methyl-6-[4-(4-hydroxy-phenyl)-1-piperazinyl]-2(3H)-benzothiazolone and 1,3-dimethyl-5-[4-(4-hydroxyphenyl)-1-piperazinyl]-2(3H)-benzimidazolone with cis-{[2-(2,4-dichlorophenyl) -2-(1H-imidazol-1-ylmethyl)]-1,3-dioxolan-4-yl}methyl meth-anesulfonate in the presence of sodium hydride furnish the title compounds.     

Reactions of Heterocumulenes with Organometallic Reagents: IX. Synthesis and Rearrangements of N-Allyl-and N-[2-(Vinyloxy)ethyl]-3-butenethioamides and -1-(methylsulfanyl)-3-buten-1-imines

Reactions of allyl and 2-(vinyloxy)ethyl isothiocyanates with alyylmagnesium bromide (THF-Et₂O, 20-30°C, 1-3 h) after hydrolysis or alkylation of adducts afforded respectively N-allyl- and N-[2-(vinyloxy)ethyl]-3-butenethioamides or N-allyl- and N-[2-(vinyloxy)ethyl]-1-(methylmercapto)-3-buten-1-imines. The reaction carried out in ethyl ether yielded instead of Nt-allyl-3-butenethioamide its isomer N-allyl-2-butenethioamide that cleanly isomerized in the system KOH-DMSOH₂O into N-(1-propenyl)-2-butenethioamide. N-[2-(vinyloxy)ethyl]-3-butenethioamide suffers a prototropic rearrangement into N-[2-(vinyloxy)ethyl]-2-butenethioamide only in the system     

Synthesis and antimalarial effects of 5,6-dichloro-2-[(4-||4-(diethylamino)-i-methylbutyl] amino||-6-methyl-2-pyrirnidinyl)amino] benzimidazole and related benzimidazoles and lH-imidazo[4,5-b] pyridines

A group of fifty-five 2-[(4-11[(dialkylamino)alkyI]amino11-6-methyl-2-pyrimidinyl)amino]-benzimidazoles (VII) was synthesized in 3-88% yield by the condensation of the requisite 2-[(2-benzimidazolyl)amino]-4-chloro-6-methylpyrimidine (VI) with the appropriate polyamine in ethanol-hydrochloric acid or neat with excess amine containing potassium iodide. The 2-[(2-benzimidazolyl)amino]-6-methyl-4-pyrirnidinol precursors (V), obtained in 11-51% yield by cyclization of 2-(cyanoamino)-4-hydroxy-6-methylpyrimidine with a suitably substituted o-phenylenediamine, were chlorinated with phosphorus oxychloride to give the intermediate 2-[(2-benzimidazolyl)amino]-4-chloro-6-rnethylpyrimidines (VI) (27-99%). Oxidation of 5,6-dichloro-2-[(4-11[4-(diethylamino)-l-methylbutyl] amino 11-6-methyl-2-pyrimidinyl) amino ]benzimidazole ( 29 ) with m-chloroperbenzoic acid gave the distal N⁴'-oxide ( 31 ) (19%). Fusion of 2,3-uiaminopyridine with 2-(cyanoamino)-4-hydroxy-6-methylpyrimidine provided 2-[(4-hydroxy-6-tnethyl-2-pyrimidinyl)amino]-lH-imitlazo[4,5-b]pyrimidine (VIII) (30%), which upon chlori-nation with phosphorus oxychloride (63%) followed by amination with i N, N-diethylethylene-diamine afforded 2-(4-11[2-(diethylamino)ethyl] amino 11-6-methyl-2-pyrimidinyl)-lH-imidazo [4,5-b]pyridine (X) (8%). Thirty-eight of the novel 2-[(4-amino-6-methyl-2-pyrimidinyl)amino]-benzimidazoles possessed “curative” activity against Plasmodium berghei at single subcutaneous doses ranging from 20.640 mg./kg. Orally, thirty-one compounds exhibited suppressive activity against P. berghei comparable with or superior to the reference drugs 1-(p-chlorophenyl)-3-(4-11[2-(diethylarnino)ethyl]amino 11-6-methyl-2-pyrimidinyl)guanidine (I) and quinine hydrochloride, while twelve of them were 5 to 28 times as potent as I and quinine hydrochloride. Eight compounds also displayed strong suppressive activity against P. gallinaceum in chicks. 5,6-Dichloro-2-[(4-112-(diethylamino)ethyl]amino11-6-methyl-2-pyrimidinyl] benzimidazole (18) showed marked activity against a cycloguanil-resistant line of P. berghei, and the most promising member of the series, namely 5,6-dichloro-2-[(4-11[4-(diethylamino)-l-methylbutyl]amino11-6-methyl-2-pyrimidinyl)amino]benzimidazole ( 29 ) (Q = 28), was designated for preclinical toxico-logical studies and clinical trial. Structure-activity relationships are discussed.     

Synthesis and spectral properties of 2,3-dihydro-2-[(o- and p-substituted)anilinylidene]-1H-4-(p-methylphenyl)-7-[(o- and p-methyl)phenoxy]-1,5-benzodiazepines

A series of twelve new 2,3-dihydro-2-[(o- and p-substituted)anilinylidene]-1H-4-(p-methylphenyl)-7-[(o- and p-methyl)phenoxy]-1,5-benzodiazepines, which have potentially useful pharmacological properties, has been synthesized by condensing the 3,3-dimercapto-1-(p-methylphenyl)-2-propen-1-one with 3,4-diaminophenyl-R-phenyl ethers. Subsequently the 1H-1,5-benzodiazepine-2-thiones obtained were treated with the (o- and p-substituted)aniline. The structure of all products was corroborated by ir, ¹H nmr, ¹³C nmr and ms.     

Umsetzung von 3-(Dimethylamino)-2H-azirinen mit 1,3-Oxazolidin-2-thion zu 3-(2-Hydroxyethyl)-2-thiohydantoinen

Reaction of 3-(Dimethylamino)-2H-azirines with 1,3-Oxazolidine-2-thione to 3-(2-Hydroxyethyl)-2- thiohydantoins The reaction of 3-(dimethylamino)-2H-azirines 1 and 1,3-oxazolidine-2-thione ( 6 ), in MeCN at room temperature, yields, after hydrolytic workup, 3-(2-hydroxyethyl)-2-thiohydantoins 7 (Scheme 2). In the case of the spirocyclic 1c , crystallization of the crude reaction mixture leads to spiro [cyclopentane-1, 7′(7′aH)-imidazo [4, 3-b] oxazole] -5′-thione 8c . The mechanism is discussed.     

Synthesis of 1-aryl-2-[2-(dimethylamino)ethyl]-1,2-dihydrochromeno[2,3-c]pyrrole-3,9-diones and their analogs

Methyl o-hydroxybenzoylpyruvate heated with N,N-dimethylethylenediamine and aromatic aldehydes affords in a high yield 5-aryl-3-hydroxy-4-(2-hydroxyphenyl)-1-[2-(dimethylamino)ethyl]-1,5-dihydro-2H-pyrrol-2-ones, which easily split off water at boiling in acetic acid and are converted into 1-aryl-2-[(2-dimethylamino)ethyl]-1,2-dihydrochromeno[2,3-c]pyrrol-3,9-diones. The developed route of synthesis provides a wide range of derivatives of 1-aryl-2-[ω-(dialkylamino)alkyl]-1,2-dihydrochromeno[2,3-c]pyrrole-3,9-diones.     

Synthesis of 1-methyl-7-(trifluoromethyl)-1H-pyrido[2,3-c][1,2]thiazin-4(3H)-one 2,2-dioxide

The reaction of methyl 2-bromo-6-(trifluoromethyl)-3-pyridinecarboxylate ( 1 ) with methanesulfonamide gave methyl 2-[(methylsulfonyl)amino]-6-(trifluoromethyl)-3-pyridine-carboxylate ( 2 ). Alkylation of compound 2 with methyl iodide followed by cyclization of the resulting methyl 2-[methyl(methylsulfonyl)amino]-6-(trifluoromethyl)-3-pyridinecarboxylate ( 3 ) yielded 1-methyl-7-(trifluoromethyl)-1H-pyrido[2,3-c][1,2]thiazin-4(3H)-one 2,2-dioxide ( 4 ). The reaction of compound 4 with α,2,4-trichlorotoluene, methyl bromopropionate, methyl iodide, 3-trifluoromethylphenyl isocyanate, phenyl isocyanate and 2,4-dichloro-5-(2-propynyloxy)phenyl isothiocyanate gave, respectively, 4-[(2,4-dichlorophenyl)methoxy]-1-methyl-7-(trifluoromethyl)-1H-pyrido[2,3-c][1,2]thiazine 2,2-dioxide ( 5 ), methyl 2-[[1-methyl-2,2-dioxido-7-(trifluoromethyl)-1H-pyrido[2,3-c][1,2]thiazin-4-yl]oxy]propanoate ( 6 ), 1,3,3-trimethyl-7-(trifluoromethyl)-1H-pyrido[2,3-c][1,2]thiazin-4(3H)-one 2,2-dioxide ( 7 ), 4-hydroxy-1-methyl-7-(trifluoromethyl)-N-[3-(trifluoromethyl)phenyl]-1H-pyrido[2,3-c][1,2]thiazine-3-carboxamide 2,2-dioxide ( 8 ), 4-hydroxy-1-methyl-7-(trifluoromethyl)-N-phenyl-1H-pyrido[2,3-c][1,2]thiazine-3-carboxamide 2,2-dioxide ( 9 ) and N-[2,4-dichloro-5-(2-propynyloxy)phenyl]-4-hydroxy-1-methyl-7-(trifluoromethyl)-1H-pyrido[2,3-c][1,2] thiazine-3-carboxamide 2,2-dioxide ( 10 ).     

Synthesis and antimalarial effects of 2-(3,4-dichloroanilino)-7-[[[(dialkylamino)alkyl]amino]]-5-methyl-s-triazolo[1,5-a]pyrimidines

3,4-Dichlorophenylisothioeyanate ( 10 ) was allowed to react with 2-methy1-2-thiopseudourea to give methyl 4-(3,4-dichlorophenyl)(dithioaltophanimidate ( 11 ) (41%), which upon treatment with hydrazine afforded 3-amino-5-(3,4-dichloroanilino)-s-triazole ( 12 ) (54-91%). Ring-closure with ethyl acetoacetale in acetic acid afforded 2-(3,4-dichloroanilino)-5-methyl-s-triazolo[ 1,5-α ]-pyrimidin-7-ol ( 13 ) (81%). Chlorination with phosphorus oxychloride gave 7-chloro-2-(3,4-dichloroanilino)-5-methyl-s-triazolo[1,5-α ]pyrimidine ( 14 ) (98%), which was condensed with various amines to yield the desired 2-(3,4-diehloroanilino)-7-¶[(dialkylamino)alkyl]arnino¶-5-methyl-s-triazolo[ 1,5-α]pyrimidines ( 6 a-d). The structures of the s-triazolo[ 1,5-α ]pyrimidines were based on nmr spectroscopy and ring stability considerations. Several of the amino-s-triazolo[ 1,5-α ]pyrimidines possessed antimalarial activity against P. berghei in mice.     

The base-promoted dehydration of rac.-trans-tetrahydro-6-hydroxy-4-[(2-(dimethylamino)ethyl]-7-(4-methoxyphenyl)-1,4-thiazepin-5(2H)-one

The base-catalyzed alkylation of rac.-trans-tetrahydro-6-hydroxy-7-(4-methoxyphenyl)-1,4-thiazepin-5(2H)-one ( 1 ) with dimethylaminoethyl chloride in dimethyl sulfoxide provided predominantly rac.-trans-tetrahydro-6-hydroxy-4-[(2-dimethylamino)ethyl]-7-(4-methoxyphenyl)-1,4-thiazepin-5(2H)-one ( 2 ) and in addition, 2,3-dihydro-4-[2-(dimethylamino)-ethyl]-7-(4-methoxyphenyl)-1,4-thiazepin-5(4H)-one ( 3 ). A plausible mechanism is postulated for the dehydration of the rac.-trans-amide 2 .     

Synthesis and anticonvulsant activity of 3-[3-[(dimethylamino)-methyl]-5-methyl-4H-1,2,4-triazol-4-yl]-4-(o-chlorobenzoyl)pyridine

Wolff-Kishner reduction of 3-amino-4-(o-chlorobenzoyl)pyridine ( 3 ) afforded 3-amino-4-(o-chlorobenzyl)pyridine ( 5 ), which on subsequent reaction with triethyl orthoformate and then acetyl hydrazide yielded 1-acetyl-2-[N-[4-(o-chlorobenzyl)pyridin-3-yl]formimidoyl]hydrazone ( 7 ). Cyclization of hydrazone 7 gave 3-(3-methyl-4H-1,2,4-triazol-4-yl)-4-(o-chlorobenzyl)pyridine ( 8 ), which on Jones oxidation yielded 3-(3-methyl-4H-1,2,4-triazol-4-yl)-4-(o-chlorobenzyl)pyridine ( 9 ). The Mannick reaction of 3-(3-methyl-4H-l,2,4-triazol-4-yl)-4-(o-chlorobenzyl)pyridine ( 9 ) with aqueous formalin and dimethylamine hydrochloride afforded 3-[3-[(dimethylamino)methyl]-5-methyl-4H-1,2,4-triazol-4-yl]-4-(o-chlorobenzoyl)-pyridine ( 10 ). 3-[3-[(Dimethylamino)methyl]-5-methyl-4H-1,2,4-triazol-4-yl]-4-(o-chlorobenzoyl)pyridine ( 10 ) exhibited good anticonvulsant activity in the subcutaneous pentylenetetrazole anticonvulsant screen indi cating that an appropriately substituted-pyridine ring moiety can serve as a bioisostere of a chlorobenzene ring with respect to anticonvulsant activity.     

Skeletal rearrangements of <Emphasis Type="Italic">cis</Emphasis>-(-)-7,8-epoxycarveol derivatives promoted by triethylsilyl trifluoromethanesulfonate

Diastereoisomeric couples of (1R,5R,6RS)-2,6-dimethyl-7-oxabicyclo[3.2.1]oct-2-en-6-ylmethanols and their epoxide precursors, (5R,2′RS)-2-methyl-5-(2-methyloxiran-2-yl)cyclohex-2-en-1-ols, in the presence of triethylsilyl trifluoromethanesulfonate underwent [3.2.1]→[3.3.1] skeletal rearrangement with formation of scalemic mixtures of (1R,5R,6R)- and (1R,5R,6S)-2,6-dimethyl-6-triethylsiloxy-8-oxabicyclo[3.3.1]non-2-enes; the (6R)-stereoisomer was isolated as individual substance.     

Methyl and Phenylmethyl 2-Acetyl-3-{[2-(dimethylamino)-1-(methoxycarbonyl)ethenyl]amino}prop-2-enoate in the Synthesis of heterocyclic systems: Preparation of 3-amino-4H-pyrido-[1,2-a]pyrimidin-4-ones

Methyl 2-acetyl-3-{[2-(dimethylamino)-1-(methoxycarbonyl)ethenyl]amino}prop-2-enoate ( 4 ) and phenyl-methyl 2-acetyl-3-{[2-(dimethylamino)-1(methoxycarbonyl)ethenyl]amino}prop-2-enoate ( 5 ) were prepared in three steps from the corresponding acetoacetic esters, and used as reagents for the preparation of N³-protected 3-amino-4H-pyrido[1,2-a]pyrimidin-4-ones 10 – 12 , 5H-thiazolo[3,2-a]pyrimidin-5-one 13 , 4H-pyrido[1,2-a]-pyridin-4-one 19 and 2H-1-benzopyran-2-ones 20 – 23 . Free 3-amino-4H-pyrido[1,2-a]pyrimidin-4-ones 24 – 26 were prepared from 10 – 12 by removal of the 2-(methoxycarbonyl)-3-oxobut-1-enyl or 3-oxo-2-[(phenyl-methoxy)carbonyl]but-1-envl as N-protecting group by various methods.     

New synthesis of 4-(1-adamantyl)-2-aryl-1,3-thiazoles from 4-(1-adamantyl)-1,2,3-thiadiazole

Treatment of 4-(1-adamantyl)-1,2,3-thiadiazole with potassium tert-butoxide generated potassium 2-(1-adamantyl)ethynethiolate which reacted with aromatic carboxylic acid chlorides to give unstable S-[2-(1-adamantyl)ethynyl] arenecarbothioates whose acid hydrolysis afforded S-[2-(1-adamantyl)-2-oxoethyl] arenecarbothioates. The latter reacted with ammonium acetate in acetic acid yielding 4-(1-adamantyl)-2-aryl-1,3-thiadiazoles. Reactions of 4-(1-adamantyl)-2-(4-chloro-3-nitrophenyl)-1,3-thiadiazole with cyclic secondary amines gave the corresponding products of nucleophilic replacement of the chlorine atom in the aromatic ring.     

Efficient synthesis of (2S)-tert-butyl 2-(2-bromopropanamido)-5-oxo-5-(tritylamino)pentanoate as a precursor of PET radiotracer [18F]FPGLN

This study describes a convenient protocol for the synthesis of (2S)-tert-butyl 2-(2-bromopropanamido)-5-oxo-5-(tritylamino)pentanoate, which can serve as an appropriate precursor of (2S)-5-amino-2-(2-[¹⁸F]fluoropropanamido)-5-oxopentanoic acid (N-(2-[¹⁸F]fluoropropionyl)-L-glutamine, [¹⁸F]FPGLN) for tumor positron emission tomography imaging. Five-step synthesis starting from L-glutamine provided the desired precursor with high yields. In addition, a simple method for the preparation of [¹⁸F]FPGLN from this easily available precursor was developed using a two-step ¹⁸F-labeling strategy.     

Synthesis of (+)-1,3:2,5-dianhydroviburnitol ((+)-(1R,2R,3S,5R,6S)-4,7-dioxatricyclo[3.2.1.03,6]octan-2-ol)

Epoxidation of (?)-(1R,2R,4R)-2-endo-cyano-7-oxabicyclo[2.2.1]hept-5-en-2-exo-yl acetate ((?)-5) followed by saponification afforded (+)-(1R,4R,5R,6R)-5,6-exo-epoxy-7-oxabicyclo[2.2.1]heptan-2-one ((+)-7). Reduction of (+)-7 with diisobutylaluminium hydride (DIBAH) gave (+)-1,3:2,5-dianhydroviburnitol ( = (+)-(1R,2R,3S,4R,6S)-4,7-dioxatricyclo[3.2.1.0^3,6]octan-2-ol; (+)-3). Hydride reductions of (±)-7 were less exo-face selective than reductions of bicyclo[2.2.1]heptan-2-one and its derivatives with NaBH₄, AlH₃, and LiAlH₄ probably because of smaller steric hindrance to endo-face hydride attack when C(5) and C(6) of the bicyclo-[2.2.1]heptan-2-one are part of an exo oxirane ring.     

Synthesis and anticonvulsant activities of 5-(2-Chlorophenyl)-7H-pyrido[4,3-f][1,2,4]triazolo[4,3-a][1,4]diazepines

A group of 5-(2-chlorophenyl)-10-(substituted)-7H-pyrido[4,3-f][1,2,4]triazolo[4,3-a][1,4]diazepines 7a-c were synthesized by the acid catalyzed reaction of 5-(2-chlorophenyl)-2-hydrazino-3H-pyrido[3,4-e]-[1,4]diazepine ( 6 ) with either trimethyl orthoformate, triethyl orthoacetate or triethyl orthobenzoate, respectively. 5-(2-Chlorophenyl)-7H-pyrido[4,3-f][1,2,4]triazolo[4,3-a][1,4]diazepine ( 7a ) and 5-(2-chlo-rophenyl)-10-methyl-7H-pyrido[4,3-f][1,2,4]triazolo[4,3-a][1,4]diazepine ( 7b ) exhibited good anticonvulsant activity in the subcutaneous metrazol anticonvulsant screen which serves as a model for absence (petit mal) epilepsy.     

Synthesis of chiral α-substituted N-[((2S)-2-hydroxy-2-phenyl)-ethyl]-2-phenylglycine derivatives by diastereocontrolled alkylation of (6 R)-2,3,5,6-tetrahydro-3,6-diaryl-N-[(2′R)-(2′-methyl)phenyl-methyl]-4H-1,4-oxazin-2-ones

The synthesis of α-substituted N-[((2S)-2-hydroxy-2-phenyl)-ethyl]-2-phenylglycine derivatives is reported. The key step of the sequence is the highly diastereoselective alkylation of (6R)-2,3,5,6-tetrahydro-3,6-diaryl-N-[(2′R)-(2′-methyl)phenylmethyl]-4H-1,4-oxazin-2-ones after deprotonation with t-BuOK. Opening of the resulting oxazinone with ethanolic KOH, followed by hydrogenolysis of the corresponding N-[(2R)-(2-methyl)phenylmethyl] compound to furnish the expected 2-phenylglycine derivative, is also described.     

Synthesis and reactions of 1-[1-oxido-2-(3,4)-pyridinyl]-2-methyloxiranes with nitrogen nucleophiles

Reaction of 2(3,4)-pyridinecarboxaldehydes (5) with ethylidenetriphenylphosphorane afford a mixture of stereoisomers Z-( 6 ) and E-1-[2(3,4)-pyridinyl]-1-propenes ( 7 ). m-Chloroperbenzoic acid oxidation of 6 and 7 yields a 60:40 mixture of Z-( 8 ) and E-1-[1-oxido-2(3,4)-pyridinyl]-2-methyloxiranes ( 9 ). The regiospecific reaction of Z-isomers 8a-c with cyclic amines as piperidine give rise to threo-1-hydroxy-1-[1-oxido-2(3,4)-pyridinyl]-2-(1-piperidino)propanes ( 10 ) while the E-isomer 9a yields erythro- 11 . On tho other hand, the E-isomers 9b and 9c having 1-oxido-3(4)-pyridinyl substituents afford erythro- 12 resulting from attack by piperidine at C-1 of the oxirane. Reductive deoxygenation using 10% palladium on charcoal and hydrogen gas effectively removed the N-oxide substituent from the threo- 10 and erythro- 11 β-aminoalcohols. Dilute solution ir spectroscopy indicated the existance of strong intramolecular hydrogen bonding in the β-aminoalcohols 10 and 11 . The assignment of relative configuration of diastereoisomers 10 and 11 was based on the magnitude of the vicinal coupling constant J where J threo is greater than J erythro.     

Structure,synthesis, and voltammetric investigation of 1-(quinolin-2-yl)-2-(pyran-2-yl)ethane-1,2-dione derivatives

By the XRD analysis the structure was established of 1-(7,8-dimethyl-4-chloroquinolin-2-yl)-2-[3,5-di(tert-butyl)-6-oxo-6H-pyran-2-yl]ethane-1,2-dione formed as a result of the oxidation of 3,5-di(tert-butyl)-6-[(Z)-2-(quinolin-2-yl)-1-hydroxyethen-1-yl]pyran-2-ones. By the cyclic voltammetry the oxidation of 1-(quinolin-2-yl)-2-(pyran-2-yl)ethane-1,2-dione derivatives was shown to proceed in two stages.     

2-[3-(Trifluoromethyl)phenyl]furo[3,2-b]pyrroles: synthesis and reactions

The synthesis and reactions of methyl 2-[3-(trifluoromethyl)phenyl]-4H-furo[3,2-b]pyrrole-5-carboxylate (1a) are described. Upon reaction with methyl iodide, benzyl chloride, or acetic anhydride, this compound gave N-substituted products 1b-d. By hydrolysis of compounds 1a-c, the corresponding acids 2a-c were formed, or by reaction with hydrazine-hydrate, the corresponding carbohydrazides 3a-c were formed. By heating 2-[3-(trifluoromethyl)phenly]-4H-furo[3,2-b]pyrrole-5-carboxylic acid (2a) in acetic anhydride, 4-acetyl-2-[3-(trifluoromethyl)phenyl]furo[3,2-b]pyrrole (4) was formed. By hydrolysis of 4, 2-[3-(trifluoromethyl)phenyl]-4H-furo[3,2-b]pyrrole (5a) was formed, and reactions with methyl iodide or benzyl chloride gave N-substituted products 5b-c. The reaction of 4 with dimethyl butynedioate gave substituted benzo[b]furan 6. Compound 3a reacted with triethyl orthoesters giving 7a-c, which afforded with phosphorus (V) sulphide the corresponding thiones 8a-c. The thiones 8a-c reacted with hydrazine hydrate to form hydrazine derivatives 9a-c. The reaction of triethyl orthoformiate with compounds 9a-c led to furo[2′,3′: 4,5]pyrrolo[1,2-d][1,2,4]triazolo[3,4-f][1,2,4]triazines 10a-c. Hydrazones 11a-c were formed from 3a-c and 5-[3-(trifluoromethyl)phenyl]furan-2-carboxaldehyde. The effect of microwave irradiation on some condensation reactions was compared with “classical” conditions. The results showed that microwave irradiation shortens the reaction time while affording comparable yields.