Studies on Organophosphorus Compounds. Part 1: Synthesis and In Vitro Antimicrobial Activity of Some New Pyrimido[5′,4′:5,6]pyrano[2,3‐d][1,3,2]thiazaphosphinine Compounds

Abstract

2,4-Bis(4-methoxyphenyl)-1,3,2,4-dithiadiphosphetane-2,4-disulfide (Lawesson's reagent, LR) reacted with pyrano[2,3-d]pyrimidine-2,4-(1H,3H)-dione derivatives in boiling acetonitrile to afford various pyrimido[5',4':5,6]pyrano[2,3-d][1,3,2]thiazaphosphinine derivatives. The structures of the target compounds were characterized by elemental analysis and spectral data. The biological activities of all synthesized compounds were tested against various microorganisms by the disk diffusion method. In general, the newly synthesized compounds showed good inhibitory effects against most of the applied microorganisms.

A Focused Review of Synthetic Applications of Lawesson’s Reagent in Organic Synthesis

“…LR can undergo ring closure with substrates containing two functional groups, forming phosphorus heterocycles, with tremendous biological activities such as insecticidal, antibacterial, antifungal, and anticancer pharmacophores. Based on the above findings and further progress in synthesizing bioactive molecules, another class of new fused P-heterocycles, a multi-functional bioactive, was formed via LR's reaction with pyrano-[2,3-d]pyrimidine-2,4-(1H,3H)-diones by Younes et al [106].…”

“…This bioactive should be further investigated in pharmaceutical and medicinal fields. d]pyrimidine-2,4-(1H, 3H)-diones by Younes et al [106].…”

“…The compound ( 105) was allowed to react with LR in boiling acetonitrile to produce (106). The reaction was proposed to move via nucleophilic attack of the amino group with LR and SH to the cyano group.…”

An Efficient Synthesis of Tetracyclic Pyrano[2,3‐d]pyrimidines

“…Of the many methods available for the synthesis of pyrano[2,3‐ d ]pyrimidines, the most widely used is the one‐pot reaction of aromatic aldehydes, compounds with active α‐hydrogen (Meldrum's acid or Malononitrile), and compounds with the pyrimidinone skeleton (barbituric acid or 2‐amino‐4,6‐dihydroxypyrimidine) . However, less previous works have employed the tricyclic pyrans to build pyrano[2,3‐ d ]pyrimidines skeleton directly.…”

The First Synthesis of [1,2]oxaphosphinino[6,5-c]pyrazoles by Thiophosphorylation of 6-Aminopyrano[2,3-c]pyrazole-5-Carbonitriles

“…For 2-amino-3-cyano-4H-pyran and chromenes, such reactions have been described in only a few recent papers. Thus, according to the known data, 1,3,2λ 5 -diazaphosphinanes 2-4 [12][13][14] or 1,3,2λ 5 -thiaazaphosphinanes 5,6 [15] were prepared through the thiophosphorylation (Scheme 2). It is noteworthy that compound 6 possess promising fungicidal activity [16], while compounds 2 possess antitumor activity and are tyrosinase inhibitors [12].…”