Novel Phosphonoacetic Acid Derivatives.Synthesis of N-(Ethoxycarbonylmethylphosphonyl)-α-Amino Esters and-α-Amino Phosphonic Acid Esters and Their Bioactivities

A series of novel phosphonoacetic acid derivatives, N-(ethoxycarbonylmethy-ethoxyphosphonyl)-α-amino acid esters and α-amino phosphonates, were synthesized via the reaction of the corresponding phosphonyl chloride with amino acid ester hydrochlorides or amino phosphonates in the presence of a base. The preliminary bioassay shows that some compounds show significant anti-viral activity against tobacco mosaic virus (TMV)

SYNTHESIS OF DERIVATIVES OF 3-β-D-XYLOPYRANOSYL-1,2,4-OXADIAZOLES

The synthesis of derivatives of 3-β-D-xylopyranosyl-1,2,4-oxadiazoles is accomplished by condensing protected β-D-xylopyranosyl amidoxime with acid anhydrides or various substituted benzoyl chlorides in good yield.The structures of now derivatives were identified by spectra and elemental analysis. The stability of 1,2,4-oxadiazole ring and mechanism of cyclization were. investigated.

SYNTHESIS OF ADENOSINE DERIVATIVES WITH CARBOXYALKYL SIDE CHAIN AT 2',3'OR 5'POSITION

Some nucleoside carhoxylic acid derivatives,such as(±)ethyl ester of griseolic acid (4)and 9-(2'-deoxy-2'-(benzyloxycarbonyl)-methylene-β-D-rihohept-2'-enofuranosyluranate)adenine (11),were synthesized.The formation of lactone of 5'-deoxy-adenosineacetic acid(AAA,3)was investigated by using different reagents for lactonization from AAA,but all of the efforts failed, and sone unexpected compounds were obtained.

REACTION OF ORGAINIC-TELLURONIUM YLIDE XI.A FACILE SYNTHESIS OF DERIVATIVES OF BISCYCLOPROPANE

Some telluronium salts react easily with 1,4-bis(3-substituted phenyl-3-oxo-1-propenyl)benzene and 1,5-disubstituted phenyl-1,4-pentadien-3 -one to afford derivatives of biscyclopropanes in 61.8-88.8% yield.

A CONVENIENT SYNTHESIS OF CYCLOOCTANE DERIVATIVES

1,5-Bismethylene cyclooctane derivatives were synthesized by the palladium catalyzed annulation reaction of 2-methylene propane-1,3-diol diacetate with compounds containing active methylene groups in the presence of BSA.

SYNTHESIS OF SOME NORTROPANE DERIVATIVES

Some novel nortropane derivatives represented by structure Ⅱ and Ⅲ were synthesized and tested for their affinity for dopamine receptors.

SYNTHESIS OF HETEROCYCLICCARBOXYLIC DERIVATIVES OF TITANOCENE MOLECULAR STRUCTURE OF (CH_3C_5H_4)Ti((?)co_2)_2

Eight comptexes (RC_5H_4)_2Ti(O_2CA_r)_2(R=H,CH_3;Ar= with 2 equiv.N_aO_2CA_r.The carboxytate ligands in the complexes coordinate to titan^um atom in monodentate mode.(CH_3C_5H_4)_2Ti(O_2CC_4H_3S-2)_2 has four-coordinate bent titanocene in which the thiophencarboxyaltes are a monodeotate ligand(Ti-0=1.981(8)A,1.926(3)A;) 0-Ti-0:91.6(8)~ ; Ti-C:2.333-2.440A).

A NEW AND EFFICIENT SYNTHESIS OF 3-IODO DERIVATIVES OF FLAVONES, THIOFLAVONES AND THIOCHROMONES

The title compounds are prepared in good yields by iodination of the corresponding flavones, thioflavones and thiochromones respectively using I_2-CAN(ceric ammonium nitrate) system. The compounds thus prepared are potentially useful precursors for the synthesis of C-3 linked binuclear compounds.

SYNTHESIS OF NEW ESTRONE DERIVATIVES OF AMINO ACIDS AND PEPTIDES

A series of estrone derivatives of amino acids and peptides haze been synthesized by different coupling reagents and the binding affinity of deblocked derivatives to the estrogen receptor of rats uteri have been measured by a comptetive radiometric bind- ing assay.

Studies on the synthesis and antifungal activity of thiochromanone derivatives

In this paper nine New Mannich bases of 6-fluoro-thiochromanone and eight new 3-substituted-6.8-dichloro thiochromanones were synthesized and their structures were confirmed by IR, H-1-NMR and elementary analysis. Most of these compounds showed excellent antifungal activity.

Investigation of Plant Systemic Organoselena Compounds (Ⅰ) Synthesis of Selena-Morpholind and its Derivatives

The synthesis of selena-morpholine and its derivatives is described.

Synthesis and Antitumor Activity of New Derivatives of Podophyllotoxin

A series of analogues of etoposide (VP-16), the C-4 alkylamino-substituted 4'demethyl-epipodophyllotoxins, have been synthesized and studied for their activity to inhibit L1210 and KB cells in vitro. Most new compounds are as active or more active than VP-16 in their inhibition of both L1210 and KB cells.

STUDIES ON THE SYNTHESIS OF D-GLUCURONIC ACID DERIVATIVES OF 2-BUTOXY-5-FLUORO-3H-4-PYRIMIDONE AND THEIR ANTICANCER ACTIVITIES

2-Butoxy-5-fluoro-3H-4-pyrimidone derivatives of D-glucuronic acid having 0-glycosidic linkage or N-glycosidic linkage were synthesized and their anticancer activity tested.Their structures were confirmed by elementary analysis,IR spectra and ~1HNMR.

BrCo (dmgh)_2Py/Zn Promoted Addition of BrCF_2CF_2CH=CHCH_2X to Alkynes: Direct Synthesis of 4,4,5,5-Tetrafluorocyclopentene Derivatives

BrCF2CF2CH=CHCH2X(x=Cl, OAc, OH) reacted smoothly with alkynes in the presence of BrCo(dmgh)2Py/Zn, giving 4,4,5,5-tetrafluorocyclopentene derivatives in moderate yields.

A NEW CONVENIENT SYNTHESIS OF S-ALKYL N,N-DIALKYL THIOPHOSPHORAMIDIC ACID DERIVATIVES

The chlorination of O,O-dialkyl N,N-dialkyl thiophosphoramidates with phosphorus oxychloride proceeds with isomerization to give S-alkyl N,N-dialkyl thiophosphoramidochloridates,which react further with various nucleophiles in the presence of base to give the title compounds.