The disclosure provides compounds having formula (I):

##STR00001##

and the pharmaceutically acceptable salts thereof, wherein R.sub.1, R.sub.2, R.sub.2, and X are as defined as set forth in the specification. Compounds having formula (I) are prodrugs that release glutamine analogs, e.g., 6-diazo-5-oxo-L-norleucine (DON). The disclosure also provides compounds having formula (I) for use in treating cancer.

The disclosure provides compounds having formula (I):

##STR00001##

and the pharmaceutically acceptable salts thereof, wherein R.sub.1, R.sub.2, R.sub.2, and X are as defined as set forth in the specification. Compounds having formula (I) are prodrugs that release glutamine analogs, e.g., 6-diazo-5-oxo-L-norleucine (DON). The disclosure also provides compounds having formula (I) for use in treating cancer.

The disclosure provides compounds having formula (I):

##STR00001##

and the pharmaceutically acceptable salts thereof, wherein R.sub.1, R.sub.2, R.sub.2, and X are as defined as set forth in the specification. Compounds having formula (I) are prodrugs that release glutamine analogs, e.g., 6-diazo-5-oxo-L-norleucine (DON). The disclosure also provides compounds having formula (I) for use in treating cancer.

The disclosure provides compounds having formula (I):

##STR00001##

and the pharmaceutically acceptable salts thereof, wherein R.sub.1, R.sub.2, R.sub.2, and X are as defined as set forth in the specification. Compounds having formula (I) are prodrugs that release glutamine analogs, e.g., 6-diazo-5-oxo-L-norleucine (DON). The disclosure also provides compounds having formula (I) for use in treating cancer.

The invention relates to the use of specific quaternised nitrogen compounds which are also subjected to specific transesterification or amidation, as a fuel and lubricant additive or kerosene additive, such as in particular as a detergent additive, for decreasing or preventing deposits in the injection systems of direct-injection diesel engines, in particular in common rail injection systems, for decreasing the fuel consumption of direct-injection diesel engines, in particular of diesel engines having common rail injection systems, and for minimizing the power loss in direct-injection diesel engines, in particular in diesel engines having common rail injection systems. The invention further relates to the use as an additive for petrol, in particular for operation of DISI engines.

The invention relates to the use of specific quaternised nitrogen compounds which are also subjected to specific transesterification or amidation, as a fuel and lubricant additive or kerosene additive, such as in particular as a detergent additive, for decreasing or preventing deposits in the injection systems of direct-injection diesel engines, in particular in common rail injection systems, for decreasing the fuel consumption of direct-injection diesel engines, in particular of diesel engines having common rail injection systems, and for minimizing the power loss in direct-injection diesel engines, in particular in diesel engines having common rail injection systems. The invention further relates to the use as an additive for petrol, in particular for operation of DISI engines.

The invention relates to the use of specific quaternised nitrogen compounds which are also subjected to specific transesterification or amidation, as a fuel and lubricant additive or kerosene additive, such as in particular as a detergent additive, for decreasing or preventing deposits in the injection systems of direct-injection diesel engines, in particular in common rail injection systems, for decreasing the fuel consumption of direct-injection diesel engines, in particular of diesel engines having common rail injection systems, and for minimizing the power loss in direct-injection diesel engines, in particular in diesel engines having common rail injection systems. The invention further relates to the use as an additive for petrol, in particular for operation of DISI engines.

The invention relates to the use of specific quaternized nitrogen compounds which are also subjected to specific transesterification or amidation, as a fuel and lubricant additive or kerosene additive, such as in particular as a detergent additive, for decreasing or preventing deposits in the injection systems of direct-injection diesel engines, in particular in common rail injection systems, for decreasing the fuel consumption of direct-injection diesel engines, in particular of diesel engines having common rail injection systems, and for minimizing the power loss in direct-injection diesel engines, in particular in diesel engines having common rail injection systems. The invention further relates to the use as an additive for petrol, in particular for operation of DISI engines.

The invention relates to the use of specific quaternized nitrogen compounds which are also subjected to specific transesterification or amidation, as a fuel and lubricant additive or kerosene additive, such as in particular as a detergent additive, for decreasing or preventing deposits in the injection systems of direct-injection diesel engines, in particular in common rail injection systems, for decreasing the fuel consumption of direct-injection diesel engines, in particular of diesel engines having common rail injection systems, and for minimizing the power loss in direct-injection diesel engines, in particular in diesel engines having common rail injection systems. The invention further relates to the use as an additive for petrol, in particular for operation of DISI engines.

The invention relates to the use of specific quaternized nitrogen compounds which are also subjected to specific transesterification or amidation, as a fuel and lubricant additive or kerosene additive, such as in particular as a detergent additive, for decreasing or preventing deposits in the injection systems of direct-injection diesel engines, in particular in common rail injection systems, for decreasing the fuel consumption of direct-injection diesel engines, in particular of diesel engines having common rail injection systems, and for minimizing the power loss in direct-injection diesel engines, in particular in diesel engines having common rail injection systems. The invention further relates to the use as an additive for petrol, in particular for operation of DISI engines.