摘要:
In a telecommunication system adapted to exchange n-bit frames according to a dynamic time division multiplexing access method for a maximum of N accessible channels, the use of a shadow time slot assignment table is eliminated by use of a circuit that includes (a) an n×p memory block to store a time slot assignment table which describes the different time slot assignments by specifying which logical channel each bit position of an n-bit frame belongs to, (b) a register having N fields with a granularity of one bit, each bit indicates the status of the corresponding logical channel associated thereto, and (c) a logic circuit connected to the memory block and register that enables or disables the transmission of the logical channel identifier to a time slot assignor depending on the status bit value.
摘要:
In a telecommunication system adapted to exchange n-bit frames according to a dynamic time division multiplexing access method for a maximum of N accessible channels, the use of a shadow time slot assignment table is eliminated by use of a circuit that includes (a) an n×p memory block to store a time slot assignment table which describes the different time slot assignments by specifying which logical channel each bit position of an n-bit frame belongs to, (b) a register having N fields with a granularity of one bit, each bit indicates the status of the corresponding logical channel associated thereto, and (c) a logic circuit connected to the memory block and register that enables or disables the transmission of the logical channel identifier to a time slot assignor depending on the status bit value.
摘要:
A process for the preparation of a compound of formula (V) and salts thereof ##STR1## wherein R.sub.1 is selected from the group consisting of a hydrogen atom, an alkyl radical, a formyl radical and an acyl radical;R.sub.2 is selected from the group consisting of an alkoxycarbonyl radical, a hydrazide radical, an acetamido radical, a hydroxymethyl radical, and an alkanoyloxy methyl radicalandR.sub.3 and R.sub.4 are the same or different and each is selected from the group consisting of a hydrogen atom, a hydroxyl radical and an alkanoyloxyl radical;which comprises the step of treating a compound of formula IV ##STR2## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are as previously defined with at least one oxidising agent selected from the group consisting of oxidising metal salts, air and oxygen.The above compounds are useful due to their antitumoral activity, and to their use as intermediates of other antitumor drugs.
摘要:
The invention relates to a telecommunication system split in a plurality of subsystems that is adapted to exchange n-bit frames there between according to the dynamic time division multiplexing (TDM) access method. According to that method, the time is split in time slots, each one corresponding to one among N logical channels, wherein N is the maximum number of logical channels that can be simultaneously opened. To each logical channel (X, . . . ) is associated an identifier (LC X, . . . ) coded on p bits. In accordance with the present invention, the improved circuit (30) first comprises a n×p memory block (31) to store the time slot assignment (TSA) table which describes the different time slot assignments by specifying which logical channel each bit position of the n-bit TDM frame (Bit1 to Bitn) it belongs to. It further comprises a register (32) having N fields with a granularity of one bit, each bit indicates the status of the corresponding logical channel associated thereto: “assigned” when it has a first value or “unassigned” when it has another value. Finally, it comprises a logic circuit (33) connected to said memory block and register that enables or disables the transmission of the logical channel identifier to a time slot assignor depending on the status bit value.
摘要:
The invention relates to new chemical compounds.They are compounds corresponding to formula Ia. ##STR1## in which: R'.sub.3 represents a hydrogen atom or a hydroxy radical; R'.sub.5 represents a hydrogen atom or a hydroxy radical; or R'.sub.3 and R'.sub.5 together represent an epoxy bridge or a double bond; R".sub.5 represents a hydrogen atom or an ethyl radical; R'.sub.7 and R'.sub.8 are the same or different and represent a hydrogen atom or a methyl, hydroxymethylene, alkoxymethylene, aryloxymethylene, aminomethylene, monoalkyl or dialkyl aminomethylene, acylmethylene, arylaminomethylene, hydroxyethyl aminomethylene, alkylthiomethylene, aryloxythiomethylene or cyanomethylene radical; R.sub.1 represents a hydrogen atom or an alkyl, formyl or acyl radical: R.sub.2 represents a hydrogen atom or an alkoxy radical; R.sub.7 represents an alkanoyloxy radical, the broken line representing an optional double bond.These compounds can be used as drugs.
摘要:
In a telecommunication system adapted to exchange n-bit frames according to a dynamic time division multiplexing access method for a maximum of N accessible channels, the use of a shadow time slot assignment table is eliminated by use of a circuit that includes (a) an n×p memory block to store a time slot assignment table which describes the different time slot assignments by specifying which logical channel each bit position of an n-bit frame belongs to, (b) a register having N fields with a granularity of one bit, each bit indicates the status of the corresponding logical channel associated thereto, and (c) a logic circuit connected to the memory block and register that enables or disables the transmission of the logical channel identifier to a time slot assignor depending on the status bit value.
摘要:
Compounds with antitumoral activity corresponding to the formula (I): ##STR1## wherein R'.sub.1 is a hydrogen atom or an alkoxy, acyl, formyl or haloacyl radical; R'.sub.2 is a hydrogen atom or an alkyl radical; R'.sub.3 and R".sub.3 are a hydrogen atom, hydroxyl radical or an alkanoyloxy radical, and together are a carbonyl group, and R'.sub.3 and R'.sub.5 together are an epoxy bridge or a double bond; R'.sub.4 is a hydrogen atom or an alkyloxycarbonyl, hydroxymethyl, alkanoyloxymethyl or acetamido radical; R'.sub.5 and R".sub.5 are a hydrogen atom or a hydroxyl, alkanoyloxyl, ethyl or 2-hydroxyethyl radical; R'.sub.6 is a hydrogen atom or an ethyl, 2-hydroxyethyl or acetyl radical; R.sub.1 is a hydrogen atom or an alkyl, formyl or acyl radical; R.sub.2 is a hydrogen atom or alkoxy radical; R.sub.3 is a hydrogen atom or a hydroxyl or alkanoyloxyl radical, and together with R.sub.4 is an epoxy bridge or a double bond; R.sub.4 is a hydrogen atom or a hydroxyl, alkanoyloxyl radical, and together with R.sub.5 is an epoxy bridge; R.sub.6 is an alkyloxycarbonyl, hydrazido, acetamido, hydroxymethyl or alkanoyloxymethyl radical; and R.sub.5 and R.sub.7 are a hydrogen atom or a hydroxyl and alkanoyloxyl radical; acid addition and quaternary ammonium salts thereof and 12-chloro derivatives thereof.
摘要:
The invention provides a process for the preparation of leurosidine or vinblastine, which comprises hydroxylating and reducing .DELTA..sup.20' dehydroxy-20' vincaleucoblastine corresponding to formula (II): ##STR1##