New mannich bases of 2-phenoxy-1,3,2-dioxaphospholanes derivatives (4R, 5R) - N’4, N’5-bis-(2-oxo-1-(piperidin- 1-ylmethyl) / (morpholino methyl) / (4-methyl piperazin-1-ylmethyl) indolin-3-ylidene) - 2-(4-substituted phenoxy)-1, 3, 2-dioxa phospholane-4, 5-dicarbohydrazide-2-oxide 6(a-g) were prepared by the condensation reaction between (4R, 5R) -2-(4-substituted phenoxy)-1, 3, 2-dioxa phospholane-4, 5-dicarbohydrazide-2-oxide 3(a-e) with Isatin (4) yielded the corresponding (4R, 5R) - N’4, N’5-bis-(2-oxo indolin-3-ylidene) - 2-(4-substituted phenoxy)-1, 3, 2- Dioxaphospholane-4, 5-dicarbohydrazide-2-oxide 5(a-e). This was allowed to undergo the Mannich reaction with different Secondary Amines namely: piperidine, morpholine and N-methyl piperazine in the presence of formaldehyde in DMF to give corresponding hydrazides 6(a-g). The structure of these newly synthesized compounds was characterized by 1H-NMR, Mass, IR, C13-NMR and P31-NMR Spectral data.These newly synthesized compounds 6(a-g) were screened for their antibacterial and antifungal activity.