Ultrasound Promoted Synthesis and Anticoagulant Activity of 2-Amino- 4H-chromen-4-ylphosphonates

Background: One of the alarming difficulties in the field of hematology is the Coagulant disorders. Despite the availability of clinically proven existing anticoagulants, their limitations have prompted a continuous search for novel anticoagulants. Objective: The primary objective of the study is to synthesize a series of 2-amino-4H-chromen-4- ylphosphonate derivatives and to test their anticoagulant activity depending on PT measurements considering commercial heparin as positive control. Method: 2-Amino-4H-chromen-4-ylphosphonates were synthesized by the reaction of salicylaldehyde derivatives (1), malononitrile (2) and dialkyl phosphite (3) in ethanol using piperazine as a catalyst by ultra-sonication at room temperature. All the title compounds (4a-l) were tested for anticoagulant activity. Results: The results of the anticoagulant activity of the title compounds revealed that 4j, 4h and 4g showed prolonged prothrombin time 87.28, 81.81 and 78.42 sec when compared with that of the standard heparin which has prothrombin time of 121.50 sec. Conclusion: The findings from this study highlight that ultrasonication of the one pot three component reaction of salicylaldehyde derivatives, malononitrile and dialkyl phosphite with piperazine as a catalyst for the synthesis of 2-amino-4H-chromen-4-ylphosphonates is the best method. In vitro coagulant assay in terms of prothrombin time (PT) revealed that 4j, 4h and 4g possess promising anticoagulant properties. Other compounds (4a-l) were also found to have significant anticoagulant effect when compared with the heparin as positive control. Thus, these compounds qualify for further clinical studies to be used as the blood anticoagulants.